* [PATCH v2] staging: sm750fb: add const qualifier to string pointer arrays
From: Francisco Maestre @ 2026-05-03 0:57 UTC (permalink / raw)
To: sudipm.mukherjee, teddy.wang, gregkh
Cc: linux-fbdev, linux-staging, linux-kernel, Francisco Maestre
Add 'const' qualifier to 'g_fbmode' and 'g_def_fbmode' pointer
declarations to make them 'static const char * const', as the
pointers themselves are not modified after initialization.
This fixes the following checkpatch.pl warning:
WARNING: static const char * array should probably be
static const char * const
Signed-off-by: Francisco Maestre <francisco@maestretorreblanca.com>
---
v2: Resend as individual patch, not part of an unrelated series.
drivers/staging/sm750fb/sm750.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/sm750fb/sm750.c b/drivers/staging/sm750fb/sm750.c
index 62f6e0cdff4d..dc9653ed2108 100644
--- a/drivers/staging/sm750fb/sm750.c
+++ b/drivers/staging/sm750fb/sm750.c
@@ -33,8 +33,8 @@
static int g_hwcursor = 1;
static int g_noaccel;
static int g_nomtrr;
-static const char *g_fbmode[] = {NULL, NULL};
-static const char *g_def_fbmode = "1024x768-32@60";
+static const char * const g_fbmode[] = {NULL, NULL};
+static const char * const g_def_fbmode = "1024x768-32@60";
static char *g_settings;
static int g_dualview;
static char *g_option;
--
2.50.1 (Apple Git-155)
^ permalink raw reply related
* Re: [PATCH] staging: sm750fb: fix const pointer array declaration
From: kernel test robot @ 2026-05-03 4:35 UTC (permalink / raw)
To: Ilai Levin, sudipm.mukherjee, teddy.wang
Cc: oe-kbuild-all, gregkh, linux-fbdev, linux-staging, linux-kernel,
Ilai Levin
In-Reply-To: <20260428122501.100696-1-levinilai972@gmail.com>
Hi Ilai,
kernel test robot noticed the following build errors:
[auto build test ERROR on staging/staging-testing]
url: https://github.com/intel-lab-lkp/linux/commits/Ilai-Levin/staging-sm750fb-fix-const-pointer-array-declaration/20260501-103116
base: staging/staging-testing
patch link: https://lore.kernel.org/r/20260428122501.100696-1-levinilai972%40gmail.com
patch subject: [PATCH] staging: sm750fb: fix const pointer array declaration
config: alpha-allyesconfig (https://download.01.org/0day-ci/archive/20260503/202605031219.ZJk8DDJm-lkp@intel.com/config)
compiler: alpha-linux-gcc (GCC) 15.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260503/202605031219.ZJk8DDJm-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605031219.ZJk8DDJm-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/staging/sm750fb/sm750.c: In function 'lynxfb_set_fbinfo':
>> drivers/staging/sm750fb/sm750.c:785:33: error: assignment of read-only location 'g_fbmode[index]'
785 | g_fbmode[index] = g_def_fbmode;
| ^
drivers/staging/sm750fb/sm750.c:787:41: error: assignment of read-only location 'g_fbmode[index]'
787 | g_fbmode[index] = g_fbmode[0];
| ^
drivers/staging/sm750fb/sm750.c: In function 'sm750fb_setup':
>> drivers/staging/sm750fb/sm750.c:896:45: error: assignment of read-only location 'g_fbmode[0]'
896 | g_fbmode[0] = opt;
| ^
drivers/staging/sm750fb/sm750.c:900:45: error: assignment of read-only location 'g_fbmode[1]'
900 | g_fbmode[1] = opt;
| ^
vim +785 drivers/staging/sm750fb/sm750.c
81dee67e215b23 Sudip Mukherjee 2015-03-03 719
81dee67e215b23 Sudip Mukherjee 2015-03-03 720 static int lynxfb_set_fbinfo(struct fb_info *info, int index)
81dee67e215b23 Sudip Mukherjee 2015-03-03 721 {
81dee67e215b23 Sudip Mukherjee 2015-03-03 722 int i;
81dee67e215b23 Sudip Mukherjee 2015-03-03 723 struct lynxfb_par *par;
e359b6a863e19f Mike Rapoport 2015-10-26 724 struct sm750_dev *sm750_dev;
81dee67e215b23 Sudip Mukherjee 2015-03-03 725 struct lynxfb_crtc *crtc;
81dee67e215b23 Sudip Mukherjee 2015-03-03 726 struct lynxfb_output *output;
81dee67e215b23 Sudip Mukherjee 2015-03-03 727 struct fb_var_screeninfo *var;
81dee67e215b23 Sudip Mukherjee 2015-03-03 728 struct fb_fix_screeninfo *fix;
81dee67e215b23 Sudip Mukherjee 2015-03-03 729
81dee67e215b23 Sudip Mukherjee 2015-03-03 730 const struct fb_videomode *pdb[] = {
81dee67e215b23 Sudip Mukherjee 2015-03-03 731 lynx750_ext, NULL, vesa_modes,
81dee67e215b23 Sudip Mukherjee 2015-03-03 732 };
81dee67e215b23 Sudip Mukherjee 2015-03-03 733 int cdb[] = {ARRAY_SIZE(lynx750_ext), 0, VESA_MODEDB_SIZE};
d0856045f0e9fc Hungyu Lin 2026-04-01 734 static const char * const fix_id[2] = {
81dee67e215b23 Sudip Mukherjee 2015-03-03 735 "sm750_fb1", "sm750_fb2",
81dee67e215b23 Sudip Mukherjee 2015-03-03 736 };
81dee67e215b23 Sudip Mukherjee 2015-03-03 737
81dee67e215b23 Sudip Mukherjee 2015-03-03 738 int ret, line_length;
81dee67e215b23 Sudip Mukherjee 2015-03-03 739
81dee67e215b23 Sudip Mukherjee 2015-03-03 740 ret = 0;
81dee67e215b23 Sudip Mukherjee 2015-03-03 741 par = (struct lynxfb_par *)info->par;
e359b6a863e19f Mike Rapoport 2015-10-26 742 sm750_dev = par->dev;
81dee67e215b23 Sudip Mukherjee 2015-03-03 743 crtc = &par->crtc;
81dee67e215b23 Sudip Mukherjee 2015-03-03 744 output = &par->output;
81dee67e215b23 Sudip Mukherjee 2015-03-03 745 var = &info->var;
81dee67e215b23 Sudip Mukherjee 2015-03-03 746 fix = &info->fix;
81dee67e215b23 Sudip Mukherjee 2015-03-03 747
81dee67e215b23 Sudip Mukherjee 2015-03-03 748 /* set index */
81dee67e215b23 Sudip Mukherjee 2015-03-03 749 par->index = index;
81dee67e215b23 Sudip Mukherjee 2015-03-03 750 output->channel = &crtc->channel;
81dee67e215b23 Sudip Mukherjee 2015-03-03 751 sm750fb_set_drv(par);
81dee67e215b23 Sudip Mukherjee 2015-03-03 752
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 753 /*
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 754 * set current cursor variable and proc pointer,
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 755 * must be set after crtc member initialized
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 756 */
fdc234d85210d9 Benjamin Philip 2021-07-28 757 crtc->cursor.offset = crtc->o_screen + crtc->vidmem_size - 1024;
e359b6a863e19f Mike Rapoport 2015-10-26 758 crtc->cursor.mmio = sm750_dev->pvReg +
e359b6a863e19f Mike Rapoport 2015-10-26 759 0x800f0 + (int)crtc->channel * 0x140;
81dee67e215b23 Sudip Mukherjee 2015-03-03 760
cd33da26036ea5 Christopher Carbone 2022-08-23 761 crtc->cursor.max_h = 64;
cd33da26036ea5 Christopher Carbone 2022-08-23 762 crtc->cursor.max_w = 64;
39f9137268ee3d Benjamin Philip 2021-07-26 763 crtc->cursor.size = crtc->cursor.max_h * crtc->cursor.max_w * 2 / 8;
e359b6a863e19f Mike Rapoport 2015-10-26 764 crtc->cursor.vstart = sm750_dev->pvMem + crtc->cursor.offset;
81dee67e215b23 Sudip Mukherjee 2015-03-03 765
3de08a2d14ff8c Lorenzo Stoakes 2015-03-20 766 memset_io(crtc->cursor.vstart, 0, crtc->cursor.size);
f7c8a046577e09 Thomas Zimmermann 2023-11-27 767 if (!g_hwcursor)
52d0744d751d8f Arnd Bergmann 2016-11-09 768 sm750_hw_cursor_disable(&crtc->cursor);
81dee67e215b23 Sudip Mukherjee 2015-03-03 769
81dee67e215b23 Sudip Mukherjee 2015-03-03 770 /* set info->fbops, must be set before fb_find_mode */
e359b6a863e19f Mike Rapoport 2015-10-26 771 if (!sm750_dev->accel_off) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 772 /* use 2d acceleration */
f7c8a046577e09 Thomas Zimmermann 2023-11-27 773 if (!g_hwcursor)
f7c8a046577e09 Thomas Zimmermann 2023-11-27 774 info->fbops = &lynxfb_ops_accel;
f7c8a046577e09 Thomas Zimmermann 2023-11-27 775 else
f7c8a046577e09 Thomas Zimmermann 2023-11-27 776 info->fbops = &lynxfb_ops_accel_with_cursor;
f7c8a046577e09 Thomas Zimmermann 2023-11-27 777 } else {
f7c8a046577e09 Thomas Zimmermann 2023-11-27 778 if (!g_hwcursor)
81dee67e215b23 Sudip Mukherjee 2015-03-03 779 info->fbops = &lynxfb_ops;
f7c8a046577e09 Thomas Zimmermann 2023-11-27 780 else
f7c8a046577e09 Thomas Zimmermann 2023-11-27 781 info->fbops = &lynxfb_ops_with_cursor;
f7c8a046577e09 Thomas Zimmermann 2023-11-27 782 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 783
81dee67e215b23 Sudip Mukherjee 2015-03-03 784 if (!g_fbmode[index]) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 @785 g_fbmode[index] = g_def_fbmode;
81dee67e215b23 Sudip Mukherjee 2015-03-03 786 if (index)
81dee67e215b23 Sudip Mukherjee 2015-03-03 787 g_fbmode[index] = g_fbmode[0];
81dee67e215b23 Sudip Mukherjee 2015-03-03 788 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 789
81dee67e215b23 Sudip Mukherjee 2015-03-03 790 for (i = 0; i < 3; i++) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 791 ret = fb_find_mode(var, info, g_fbmode[index],
81dee67e215b23 Sudip Mukherjee 2015-03-03 792 pdb[i], cdb[i], NULL, 8);
81dee67e215b23 Sudip Mukherjee 2015-03-03 793
db7fb3588ab492 Artem Lytkin 2026-02-23 794 if (ret == 1 || ret == 2)
81dee67e215b23 Sudip Mukherjee 2015-03-03 795 break;
81dee67e215b23 Sudip Mukherjee 2015-03-03 796 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 797
81dee67e215b23 Sudip Mukherjee 2015-03-03 798 /* set par */
81dee67e215b23 Sudip Mukherjee 2015-03-03 799 par->info = info;
81dee67e215b23 Sudip Mukherjee 2015-03-03 800
81dee67e215b23 Sudip Mukherjee 2015-03-03 801 /* set info */
e3a3f9f5123683 Mike Rapoport 2015-10-26 802 line_length = ALIGN((var->xres_virtual * var->bits_per_pixel / 8),
e3a3f9f5123683 Mike Rapoport 2015-10-26 803 crtc->line_pad);
81dee67e215b23 Sudip Mukherjee 2015-03-03 804
81dee67e215b23 Sudip Mukherjee 2015-03-03 805 info->pseudo_palette = &par->pseudo_palette[0];
cc59bde1c920ab Benjamin Philip 2021-07-28 806 info->screen_base = crtc->v_screen;
81dee67e215b23 Sudip Mukherjee 2015-03-03 807 info->screen_size = line_length * var->yres_virtual;
81dee67e215b23 Sudip Mukherjee 2015-03-03 808
81dee67e215b23 Sudip Mukherjee 2015-03-03 809 /* set info->fix */
81dee67e215b23 Sudip Mukherjee 2015-03-03 810 fix->type = FB_TYPE_PACKED_PIXELS;
81dee67e215b23 Sudip Mukherjee 2015-03-03 811 fix->type_aux = 0;
81dee67e215b23 Sudip Mukherjee 2015-03-03 812 fix->xpanstep = crtc->xpanstep;
81dee67e215b23 Sudip Mukherjee 2015-03-03 813 fix->ypanstep = crtc->ypanstep;
81dee67e215b23 Sudip Mukherjee 2015-03-03 814 fix->ywrapstep = crtc->ywrapstep;
81dee67e215b23 Sudip Mukherjee 2015-03-03 815 fix->accel = FB_ACCEL_SMI;
81dee67e215b23 Sudip Mukherjee 2015-03-03 816
8c475735085a7d Tim Wassink 2025-12-21 817 strscpy(fix->id, fix_id[index], sizeof(fix->id));
81dee67e215b23 Sudip Mukherjee 2015-03-03 818
fdc234d85210d9 Benjamin Philip 2021-07-28 819 fix->smem_start = crtc->o_screen + sm750_dev->vidmem_start;
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 820 /*
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 821 * according to mmap experiment from user space application,
81dee67e215b23 Sudip Mukherjee 2015-03-03 822 * fix->mmio_len should not larger than virtual size
81dee67e215b23 Sudip Mukherjee 2015-03-03 823 * (xres_virtual x yres_virtual x ByPP)
81dee67e215b23 Sudip Mukherjee 2015-03-03 824 * Below line maybe buggy when user mmap fb dev node and write
81dee67e215b23 Sudip Mukherjee 2015-03-03 825 * data into the bound over virtual size
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 826 */
81dee67e215b23 Sudip Mukherjee 2015-03-03 827 fix->smem_len = crtc->vidmem_size;
81dee67e215b23 Sudip Mukherjee 2015-03-03 828 info->screen_size = fix->smem_len;
81dee67e215b23 Sudip Mukherjee 2015-03-03 829 fix->line_length = line_length;
e359b6a863e19f Mike Rapoport 2015-10-26 830 fix->mmio_start = sm750_dev->vidreg_start;
e359b6a863e19f Mike Rapoport 2015-10-26 831 fix->mmio_len = sm750_dev->vidreg_size;
b610e1193a917f Matej Dujava 2020-04-30 832
b610e1193a917f Matej Dujava 2020-04-30 833 lynxfb_set_visual_mode(info);
81dee67e215b23 Sudip Mukherjee 2015-03-03 834
81dee67e215b23 Sudip Mukherjee 2015-03-03 835 /* set var */
81dee67e215b23 Sudip Mukherjee 2015-03-03 836 var->activate = FB_ACTIVATE_NOW;
81dee67e215b23 Sudip Mukherjee 2015-03-03 837 var->accel_flags = 0;
81dee67e215b23 Sudip Mukherjee 2015-03-03 838 var->vmode = FB_VMODE_NONINTERLACED;
81dee67e215b23 Sudip Mukherjee 2015-03-03 839
61c507cf652da1 Michel von Czettritz 2015-03-26 840 ret = fb_alloc_cmap(&info->cmap, 256, 0);
61c507cf652da1 Michel von Czettritz 2015-03-26 841 if (ret < 0) {
fbab250eb51d6d Artem Lytkin 2026-02-07 842 dev_err(info->device, "Could not allocate memory for cmap.\n");
81dee67e215b23 Sudip Mukherjee 2015-03-03 843 goto exit;
81dee67e215b23 Sudip Mukherjee 2015-03-03 844 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 845
81dee67e215b23 Sudip Mukherjee 2015-03-03 846 exit:
81dee67e215b23 Sudip Mukherjee 2015-03-03 847 lynxfb_ops_check_var(var, info);
81dee67e215b23 Sudip Mukherjee 2015-03-03 848 return ret;
81dee67e215b23 Sudip Mukherjee 2015-03-03 849 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 850
81dee67e215b23 Sudip Mukherjee 2015-03-03 851 /* chip specific g_option configuration routine */
700591a9adc8b1 Mike Rapoport 2015-10-26 852 static void sm750fb_setup(struct sm750_dev *sm750_dev, char *src)
81dee67e215b23 Sudip Mukherjee 2015-03-03 853 {
81dee67e215b23 Sudip Mukherjee 2015-03-03 854 char *opt;
81dee67e215b23 Sudip Mukherjee 2015-03-03 855 int swap;
81dee67e215b23 Sudip Mukherjee 2015-03-03 856
81dee67e215b23 Sudip Mukherjee 2015-03-03 857 swap = 0;
81dee67e215b23 Sudip Mukherjee 2015-03-03 858
cc34db609ff98c Madhumitha Sundar 2026-01-27 859 sm750_dev->init_parm.chip_clk = 0;
cc34db609ff98c Madhumitha Sundar 2026-01-27 860 sm750_dev->init_parm.mem_clk = 0;
cc34db609ff98c Madhumitha Sundar 2026-01-27 861 sm750_dev->init_parm.master_clk = 0;
cc34db609ff98c Madhumitha Sundar 2026-01-27 862 sm750_dev->init_parm.powerMode = 0;
cc34db609ff98c Madhumitha Sundar 2026-01-27 863 sm750_dev->init_parm.setAllEngOff = 0;
cc34db609ff98c Madhumitha Sundar 2026-01-27 864 sm750_dev->init_parm.resetMemory = 1;
81dee67e215b23 Sudip Mukherjee 2015-03-03 865
81dee67e215b23 Sudip Mukherjee 2015-03-03 866 /* defaultly turn g_hwcursor on for both view */
81dee67e215b23 Sudip Mukherjee 2015-03-03 867 g_hwcursor = 3;
81dee67e215b23 Sudip Mukherjee 2015-03-03 868
81dee67e215b23 Sudip Mukherjee 2015-03-03 869 if (!src || !*src) {
c56de0967a658c Elise Lennion 2016-10-31 870 dev_warn(&sm750_dev->pdev->dev, "no specific g_option.\n");
81dee67e215b23 Sudip Mukherjee 2015-03-03 871 goto NO_PARAM;
81dee67e215b23 Sudip Mukherjee 2015-03-03 872 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 873
0fa96e39279988 Sudip Mukherjee 2015-03-10 874 while ((opt = strsep(&src, ":")) != NULL && *opt != 0) {
c56de0967a658c Elise Lennion 2016-10-31 875 dev_info(&sm750_dev->pdev->dev, "opt=%s\n", opt);
c56de0967a658c Elise Lennion 2016-10-31 876 dev_info(&sm750_dev->pdev->dev, "src=%s\n", src);
81dee67e215b23 Sudip Mukherjee 2015-03-03 877
144634a6b42146 Katie Dunne 2017-02-19 878 if (!strncmp(opt, "swap", strlen("swap"))) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 879 swap = 1;
144634a6b42146 Katie Dunne 2017-02-19 880 } else if (!strncmp(opt, "nocrt", strlen("nocrt"))) {
1757d106a9ce8c Mike Rapoport 2015-10-26 881 sm750_dev->nocrt = 1;
144634a6b42146 Katie Dunne 2017-02-19 882 } else if (!strncmp(opt, "36bit", strlen("36bit"))) {
94c938a0c15863 Shubham Chakraborty 2026-04-07 883 sm750_dev->pnltype = SM750_DOUBLE_TFT;
144634a6b42146 Katie Dunne 2017-02-19 884 } else if (!strncmp(opt, "18bit", strlen("18bit"))) {
94c938a0c15863 Shubham Chakraborty 2026-04-07 885 sm750_dev->pnltype = SM750_DUAL_TFT;
144634a6b42146 Katie Dunne 2017-02-19 886 } else if (!strncmp(opt, "24bit", strlen("24bit"))) {
94c938a0c15863 Shubham Chakraborty 2026-04-07 887 sm750_dev->pnltype = SM750_24TFT;
144634a6b42146 Katie Dunne 2017-02-19 888 } else if (!strncmp(opt, "nohwc0", strlen("nohwc0"))) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 889 g_hwcursor &= ~0x1;
144634a6b42146 Katie Dunne 2017-02-19 890 } else if (!strncmp(opt, "nohwc1", strlen("nohwc1"))) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 891 g_hwcursor &= ~0x2;
144634a6b42146 Katie Dunne 2017-02-19 892 } else if (!strncmp(opt, "nohwc", strlen("nohwc"))) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 893 g_hwcursor = 0;
144634a6b42146 Katie Dunne 2017-02-19 894 } else {
81dee67e215b23 Sudip Mukherjee 2015-03-03 895 if (!g_fbmode[0]) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 @896 g_fbmode[0] = opt;
cee9ba1c30d051 Abdul Rauf 2017-01-08 897 dev_info(&sm750_dev->pdev->dev,
cee9ba1c30d051 Abdul Rauf 2017-01-08 898 "find fbmode0 : %s\n", g_fbmode[0]);
81dee67e215b23 Sudip Mukherjee 2015-03-03 899 } else if (!g_fbmode[1]) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 900 g_fbmode[1] = opt;
cee9ba1c30d051 Abdul Rauf 2017-01-08 901 dev_info(&sm750_dev->pdev->dev,
cee9ba1c30d051 Abdul Rauf 2017-01-08 902 "find fbmode1 : %s\n", g_fbmode[1]);
81dee67e215b23 Sudip Mukherjee 2015-03-03 903 } else {
c56de0967a658c Elise Lennion 2016-10-31 904 dev_warn(&sm750_dev->pdev->dev, "How many view you wann set?\n");
81dee67e215b23 Sudip Mukherjee 2015-03-03 905 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 906 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 907 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 908
81dee67e215b23 Sudip Mukherjee 2015-03-03 909 NO_PARAM:
e359b6a863e19f Mike Rapoport 2015-10-26 910 if (sm750_dev->revid != SM750LE_REVISION_ID) {
a3f92cc94c6126 Mike Rapoport 2016-01-17 911 if (sm750_dev->fb_count > 1) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 912 if (swap)
1757d106a9ce8c Mike Rapoport 2015-10-26 913 sm750_dev->dataflow = sm750_dual_swap;
81dee67e215b23 Sudip Mukherjee 2015-03-03 914 else
1757d106a9ce8c Mike Rapoport 2015-10-26 915 sm750_dev->dataflow = sm750_dual_normal;
81dee67e215b23 Sudip Mukherjee 2015-03-03 916 } else {
81dee67e215b23 Sudip Mukherjee 2015-03-03 917 if (swap)
1757d106a9ce8c Mike Rapoport 2015-10-26 918 sm750_dev->dataflow = sm750_simul_sec;
81dee67e215b23 Sudip Mukherjee 2015-03-03 919 else
1757d106a9ce8c Mike Rapoport 2015-10-26 920 sm750_dev->dataflow = sm750_simul_pri;
81dee67e215b23 Sudip Mukherjee 2015-03-03 921 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 922 } else {
81dee67e215b23 Sudip Mukherjee 2015-03-03 923 /* SM750LE only have one crt channel */
1757d106a9ce8c Mike Rapoport 2015-10-26 924 sm750_dev->dataflow = sm750_simul_sec;
81dee67e215b23 Sudip Mukherjee 2015-03-03 925 /* sm750le do not have complex attributes */
1757d106a9ce8c Mike Rapoport 2015-10-26 926 sm750_dev->nocrt = 0;
81dee67e215b23 Sudip Mukherjee 2015-03-03 927 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 928 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 929
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply
* [PATCH] video: fbdev: remove Hercules monochrome ISA graphics adapter driver
From: Ethan Nelson-Moore @ 2026-05-03 4:56 UTC (permalink / raw)
To: linux-fbdev
Cc: Ferenc Bakonyi, Ethan Nelson-Moore, Helge Deller, Jakub Kicinski,
Andrew Morton, Namjae Jeon, Hisam Mehboob,
Martin Kepplinger-Novaković, Diego Viola, Thomas Zimmermann,
Wei Liu, Prasanna Kumar T S M, robgithub, Hardik Phalet
The hgafb supports graphics adapters compatible with the Hercules
adapter from 1984. These were ISA cards or onboard devices that
supported monochrome 720x348 graphics. This driver was created in 1999
by Ferenc Bakonyi. In the entire Git history (since Linux 2.6.12-rc2),
there has only been one commit in 2010 which indicated that the driver
was in use, commit 529ed806d454 ("video: Fix the HGA framebuffer
driver"). The commit message states:
Only tested with fbcon, since most fbdev-based software appears
to only support 12bpp and up. It does not appear that this driver has
worked for at least the entire 2.6.x series, perhaps since 2002.
Given the age and limited capabilities of the hardware and the lack of
users, remove this driver and move the former maintainer to CREDITS.
Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
---
CREDITS | 3 +
MAINTAINERS | 7 -
drivers/video/fbdev/Kconfig | 13 -
drivers/video/fbdev/Makefile | 1 -
drivers/video/fbdev/hgafb.c | 685 -----------------------------------
5 files changed, 3 insertions(+), 706 deletions(-)
delete mode 100644 drivers/video/fbdev/hgafb.c
diff --git a/CREDITS b/CREDITS
index 17962bdd6dbd..59d5de3eeb5b 100644
--- a/CREDITS
+++ b/CREDITS
@@ -197,6 +197,9 @@ S: Hauptstrasse 19
S: 79837 St. Blasien
S: Germany
+N: Ferenc Bakonyi
+D: Hercules graphics adapter framebuffer driver
+
N: Krishna Balasubramanian
E: balasub@cis.ohio-state.edu
D: Wrote SYS V IPC (part of standard kernel since 0.99.10)
diff --git a/MAINTAINERS b/MAINTAINERS
index 882214b0e7db..3194befa6a13 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11373,13 +11373,6 @@ F: Documentation/filesystems/hfsplus.rst
F: fs/hfsplus/
F: include/linux/hfs_common.h
-HGA FRAMEBUFFER DRIVER
-M: Ferenc Bakonyi <fero@drama.obuda.kando.hu>
-L: linux-nvidia@lists.surfsouth.com
-S: Maintained
-W: http://drama.obuda.kando.hu/~fero/cgi-bin/hgafb.shtml
-F: drivers/video/fbdev/hgafb.c
-
HIBERNATION (aka Software Suspend, aka swsusp)
M: "Rafael J. Wysocki" <rafael@kernel.org>
R: Pavel Machek <pavel@kernel.org>
diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
index 1c73d560f196..085d3a202148 100644
--- a/drivers/video/fbdev/Kconfig
+++ b/drivers/video/fbdev/Kconfig
@@ -453,19 +453,6 @@ config FB_N411
This enables support for the Apollo display controller in its
Hecuba form using the n411 devkit.
-config FB_HGA
- tristate "Hercules mono graphics support"
- depends on FB && X86
- select FB_IOMEM_FOPS
- help
- Say Y here if you have a Hercules mono graphics card.
-
- To compile this driver as a module, choose M here: the
- module will be called hgafb.
-
- As this card technology is at least 25 years old,
- most people will answer N here.
-
config FB_GBE
bool "SGI Graphics Backend frame buffer support"
depends on (FB = y) && HAS_IOMEM
diff --git a/drivers/video/fbdev/Makefile b/drivers/video/fbdev/Makefile
index 36a18d958ba0..0b17c878154d 100644
--- a/drivers/video/fbdev/Makefile
+++ b/drivers/video/fbdev/Makefile
@@ -59,7 +59,6 @@ obj-$(CONFIG_FB_ATARI) += atafb.o c2p_iplan2.o atafb_mfb.o \
obj-$(CONFIG_FB_MAC) += macfb.o
obj-$(CONFIG_FB_HECUBA) += hecubafb.o
obj-$(CONFIG_FB_N411) += n411.o
-obj-$(CONFIG_FB_HGA) += hgafb.o
obj-$(CONFIG_FB_XVR500) += sunxvr500.o
obj-$(CONFIG_FB_XVR2500) += sunxvr2500.o
obj-$(CONFIG_FB_XVR1000) += sunxvr1000.o
diff --git a/drivers/video/fbdev/hgafb.c b/drivers/video/fbdev/hgafb.c
deleted file mode 100644
index d32fd1c5217c..000000000000
--- a/drivers/video/fbdev/hgafb.c
+++ /dev/null
@@ -1,685 +0,0 @@
-/*
- * linux/drivers/video/hgafb.c -- Hercules graphics adaptor frame buffer device
- *
- * Created 25 Nov 1999 by Ferenc Bakonyi (fero@drama.obuda.kando.hu)
- * Based on skeletonfb.c by Geert Uytterhoeven and
- * mdacon.c by Andrew Apted
- *
- * History:
- *
- * - Revision 0.1.8 (23 Oct 2002): Ported to new framebuffer api.
- *
- * - Revision 0.1.7 (23 Jan 2001): fix crash resulting from MDA only cards
- * being detected as Hercules. (Paul G.)
- * - Revision 0.1.6 (17 Aug 2000): new style structs
- * documentation
- * - Revision 0.1.5 (13 Mar 2000): spinlocks instead of saveflags();cli();etc
- * minor fixes
- * - Revision 0.1.4 (24 Jan 2000): fixed a bug in hga_card_detect() for
- * HGA-only systems
- * - Revision 0.1.3 (22 Jan 2000): modified for the new fb_info structure
- * screen is cleared after rmmod
- * virtual resolutions
- * module parameter 'nologo={0|1}'
- * the most important: boot logo :)
- * - Revision 0.1.0 (6 Dec 1999): faster scrolling and minor fixes
- * - First release (25 Nov 1999)
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file COPYING in the main directory of this archive
- * for more details.
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/spinlock.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/delay.h>
-#include <linux/fb.h>
-#include <linux/init.h>
-#include <linux/ioport.h>
-#include <linux/platform_device.h>
-#include <asm/io.h>
-#include <asm/vga.h>
-
-#if 0
-#define DPRINTK(args...) printk(KERN_DEBUG __FILE__": " ##args)
-#else
-#define DPRINTK(args...)
-#endif
-
-#if 0
-#define CHKINFO(ret) if (info != &fb_info) { printk(KERN_DEBUG __FILE__": This should never happen, line:%d \n", __LINE__); return ret; }
-#else
-#define CHKINFO(ret)
-#endif
-
-/* Description of the hardware layout */
-
-static void __iomem *hga_vram; /* Base of video memory */
-static unsigned long hga_vram_len; /* Size of video memory */
-
-#define HGA_ROWADDR(row) ((row%4)*8192 + (row>>2)*90)
-#define HGA_TXT 0
-#define HGA_GFX 1
-
-static inline u8 __iomem * rowaddr(struct fb_info *info, u_int row)
-{
- return info->screen_base + HGA_ROWADDR(row);
-}
-
-static int hga_mode = -1; /* 0 = txt, 1 = gfx mode */
-
-static enum { TYPE_HERC, TYPE_HERCPLUS, TYPE_HERCCOLOR } hga_type;
-static char *hga_type_name;
-
-#define HGA_INDEX_PORT 0x3b4 /* Register select port */
-#define HGA_VALUE_PORT 0x3b5 /* Register value port */
-#define HGA_MODE_PORT 0x3b8 /* Mode control port */
-#define HGA_STATUS_PORT 0x3ba /* Status and Config port */
-#define HGA_GFX_PORT 0x3bf /* Graphics control port */
-
-/* HGA register values */
-
-#define HGA_CURSOR_BLINKING 0x00
-#define HGA_CURSOR_OFF 0x20
-#define HGA_CURSOR_SLOWBLINK 0x60
-
-#define HGA_MODE_GRAPHICS 0x02
-#define HGA_MODE_VIDEO_EN 0x08
-#define HGA_MODE_BLINK_EN 0x20
-#define HGA_MODE_GFX_PAGE1 0x80
-
-#define HGA_STATUS_HSYNC 0x01
-#define HGA_STATUS_VSYNC 0x80
-#define HGA_STATUS_VIDEO 0x08
-
-#define HGA_CONFIG_COL132 0x08
-#define HGA_GFX_MODE_EN 0x01
-#define HGA_GFX_PAGE_EN 0x02
-
-/* Global locks */
-
-static DEFINE_SPINLOCK(hga_reg_lock);
-
-/* Framebuffer driver structures */
-
-static const struct fb_var_screeninfo hga_default_var = {
- .xres = 720,
- .yres = 348,
- .xres_virtual = 720,
- .yres_virtual = 348,
- .bits_per_pixel = 1,
- .red = {0, 1, 0},
- .green = {0, 1, 0},
- .blue = {0, 1, 0},
- .transp = {0, 0, 0},
- .height = -1,
- .width = -1,
-};
-
-static struct fb_fix_screeninfo hga_fix = {
- .id = "HGA",
- .type = FB_TYPE_PACKED_PIXELS, /* (not sure) */
- .visual = FB_VISUAL_MONO10,
- .xpanstep = 8,
- .ypanstep = 8,
- .line_length = 90,
- .accel = FB_ACCEL_NONE
-};
-
-/* Don't assume that tty1 will be the initial current console. */
-static int release_io_port = 0;
-static int release_io_ports = 0;
-static bool nologo = 0;
-
-/* -------------------------------------------------------------------------
- *
- * Low level hardware functions
- *
- * ------------------------------------------------------------------------- */
-
-static void write_hga_b(unsigned int val, unsigned char reg)
-{
- outb_p(reg, HGA_INDEX_PORT);
- outb_p(val, HGA_VALUE_PORT);
-}
-
-static void write_hga_w(unsigned int val, unsigned char reg)
-{
- outb_p(reg, HGA_INDEX_PORT); outb_p(val >> 8, HGA_VALUE_PORT);
- outb_p(reg+1, HGA_INDEX_PORT); outb_p(val & 0xff, HGA_VALUE_PORT);
-}
-
-static int test_hga_b(unsigned char val, unsigned char reg)
-{
- outb_p(reg, HGA_INDEX_PORT);
- outb (val, HGA_VALUE_PORT);
- udelay(20); val = (inb_p(HGA_VALUE_PORT) == val);
- return val;
-}
-
-static void hga_clear_screen(void)
-{
- unsigned char fillchar = 0xbf; /* magic */
- unsigned long flags;
-
- spin_lock_irqsave(&hga_reg_lock, flags);
- if (hga_mode == HGA_TXT)
- fillchar = ' ';
- else if (hga_mode == HGA_GFX)
- fillchar = 0x00;
- spin_unlock_irqrestore(&hga_reg_lock, flags);
- if (fillchar != 0xbf)
- memset_io(hga_vram, fillchar, hga_vram_len);
-}
-
-static void hga_txt_mode(void)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&hga_reg_lock, flags);
- outb_p(HGA_MODE_VIDEO_EN | HGA_MODE_BLINK_EN, HGA_MODE_PORT);
- outb_p(0x00, HGA_GFX_PORT);
- outb_p(0x00, HGA_STATUS_PORT);
-
- write_hga_b(0x61, 0x00); /* horizontal total */
- write_hga_b(0x50, 0x01); /* horizontal displayed */
- write_hga_b(0x52, 0x02); /* horizontal sync pos */
- write_hga_b(0x0f, 0x03); /* horizontal sync width */
-
- write_hga_b(0x19, 0x04); /* vertical total */
- write_hga_b(0x06, 0x05); /* vertical total adjust */
- write_hga_b(0x19, 0x06); /* vertical displayed */
- write_hga_b(0x19, 0x07); /* vertical sync pos */
-
- write_hga_b(0x02, 0x08); /* interlace mode */
- write_hga_b(0x0d, 0x09); /* maximum scanline */
- write_hga_b(0x0c, 0x0a); /* cursor start */
- write_hga_b(0x0d, 0x0b); /* cursor end */
-
- write_hga_w(0x0000, 0x0c); /* start address */
- write_hga_w(0x0000, 0x0e); /* cursor location */
-
- hga_mode = HGA_TXT;
- spin_unlock_irqrestore(&hga_reg_lock, flags);
-}
-
-static void hga_gfx_mode(void)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&hga_reg_lock, flags);
- outb_p(0x00, HGA_STATUS_PORT);
- outb_p(HGA_GFX_MODE_EN, HGA_GFX_PORT);
- outb_p(HGA_MODE_VIDEO_EN | HGA_MODE_GRAPHICS, HGA_MODE_PORT);
-
- write_hga_b(0x35, 0x00); /* horizontal total */
- write_hga_b(0x2d, 0x01); /* horizontal displayed */
- write_hga_b(0x2e, 0x02); /* horizontal sync pos */
- write_hga_b(0x07, 0x03); /* horizontal sync width */
-
- write_hga_b(0x5b, 0x04); /* vertical total */
- write_hga_b(0x02, 0x05); /* vertical total adjust */
- write_hga_b(0x57, 0x06); /* vertical displayed */
- write_hga_b(0x57, 0x07); /* vertical sync pos */
-
- write_hga_b(0x02, 0x08); /* interlace mode */
- write_hga_b(0x03, 0x09); /* maximum scanline */
- write_hga_b(0x00, 0x0a); /* cursor start */
- write_hga_b(0x00, 0x0b); /* cursor end */
-
- write_hga_w(0x0000, 0x0c); /* start address */
- write_hga_w(0x0000, 0x0e); /* cursor location */
-
- hga_mode = HGA_GFX;
- spin_unlock_irqrestore(&hga_reg_lock, flags);
-}
-
-static void hga_show_logo(struct fb_info *info)
-{
-/*
- void __iomem *dest = hga_vram;
- char *logo = linux_logo_bw;
- int x, y;
-
- for (y = 134; y < 134 + 80 ; y++) * this needs some cleanup *
- for (x = 0; x < 10 ; x++)
- writeb(~*(logo++),(dest + HGA_ROWADDR(y) + x + 40));
-*/
-}
-
-static void hga_pan(unsigned int xoffset, unsigned int yoffset)
-{
- unsigned int base;
- unsigned long flags;
-
- base = (yoffset / 8) * 90 + xoffset;
- spin_lock_irqsave(&hga_reg_lock, flags);
- write_hga_w(base, 0x0c); /* start address */
- spin_unlock_irqrestore(&hga_reg_lock, flags);
- DPRINTK("hga_pan: base:%d\n", base);
-}
-
-static void hga_blank(int blank_mode)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&hga_reg_lock, flags);
- if (blank_mode) {
- outb_p(0x00, HGA_MODE_PORT); /* disable video */
- } else {
- outb_p(HGA_MODE_VIDEO_EN | HGA_MODE_GRAPHICS, HGA_MODE_PORT);
- }
- spin_unlock_irqrestore(&hga_reg_lock, flags);
-}
-
-static int hga_card_detect(struct platform_device *pdev)
-{
- int count = 0;
- void __iomem *p, *q;
- unsigned short p_save, q_save;
-
- hga_vram_len = 0x08000;
-
- if (!devm_request_mem_region(&pdev->dev, 0xb0000, hga_vram_len, "hgafb")) {
- dev_err(&pdev->dev, "cannot reserve video memory at 0xb0000\n");
- return -EBUSY;
- }
-
- hga_vram = ioremap(0xb0000, hga_vram_len);
- if (!hga_vram)
- return -ENOMEM;
-
- if (request_region(0x3b0, 12, "hgafb"))
- release_io_ports = 1;
- if (request_region(0x3bf, 1, "hgafb"))
- release_io_port = 1;
-
- /* do a memory check */
-
- p = hga_vram;
- q = hga_vram + 0x01000;
-
- p_save = readw(p); q_save = readw(q);
-
- writew(0xaa55, p); if (readw(p) == 0xaa55) count++;
- writew(0x55aa, p); if (readw(p) == 0x55aa) count++;
- writew(p_save, p);
-
- if (count != 2)
- goto error;
-
- /* Ok, there is definitely a card registering at the correct
- * memory location, so now we do an I/O port test.
- */
-
- if (!test_hga_b(0x66, 0x0f)) /* cursor low register */
- goto error;
-
- if (!test_hga_b(0x99, 0x0f)) /* cursor low register */
- goto error;
-
- /* See if the card is a Hercules, by checking whether the vsync
- * bit of the status register is changing. This test lasts for
- * approximately 1/10th of a second.
- */
-
- p_save = q_save = inb_p(HGA_STATUS_PORT) & HGA_STATUS_VSYNC;
-
- for (count=0; count < 50000 && p_save == q_save; count++) {
- q_save = inb(HGA_STATUS_PORT) & HGA_STATUS_VSYNC;
- udelay(2);
- }
-
- if (p_save == q_save)
- goto error;
-
- switch (inb_p(HGA_STATUS_PORT) & 0x70) {
- case 0x10:
- hga_type = TYPE_HERCPLUS;
- hga_type_name = "HerculesPlus";
- break;
- case 0x50:
- hga_type = TYPE_HERCCOLOR;
- hga_type_name = "HerculesColor";
- break;
- default:
- hga_type = TYPE_HERC;
- hga_type_name = "Hercules";
- break;
- }
- return 0;
-error:
- if (release_io_ports)
- release_region(0x3b0, 12);
- if (release_io_port)
- release_region(0x3bf, 1);
-
- iounmap(hga_vram);
-
- pr_err("hgafb: HGA card not detected.\n");
-
- return -EINVAL;
-}
-
-/**
- * hgafb_open - open the framebuffer device
- * @info: pointer to fb_info object containing info for current hga board
- * @init: open by console system or userland.
- *
- * Returns: %0
- */
-
-static int hgafb_open(struct fb_info *info, int init)
-{
- hga_gfx_mode();
- hga_clear_screen();
- if (!nologo) hga_show_logo(info);
- return 0;
-}
-
-/**
- * hgafb_release - open the framebuffer device
- * @info: pointer to fb_info object containing info for current hga board
- * @init: open by console system or userland.
- *
- * Returns: %0
- */
-
-static int hgafb_release(struct fb_info *info, int init)
-{
- hga_txt_mode();
- hga_clear_screen();
- return 0;
-}
-
-/**
- * hgafb_setcolreg - set color registers
- * @regno:register index to set
- * @red:red value, unused
- * @green:green value, unused
- * @blue:blue value, unused
- * @transp:transparency value, unused
- * @info:unused
- *
- * This callback function is used to set the color registers of a HGA
- * board. Since we have only two fixed colors only @regno is checked.
- * A zero is returned on success and 1 for failure.
- *
- * Returns: %0
- */
-
-static int hgafb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
- u_int transp, struct fb_info *info)
-{
- if (regno > 1)
- return 1;
- return 0;
-}
-
-/**
- * hgafb_pan_display - pan or wrap the display
- * @var:contains new xoffset, yoffset and vmode values
- * @info:pointer to fb_info object containing info for current hga board
- *
- * This function looks only at xoffset, yoffset and the %FB_VMODE_YWRAP
- * flag in @var. If input parameters are correct it calls hga_pan() to
- * program the hardware. @info->var is updated to the new values.
- *
- * Returns: %0 on success or %-EINVAL for failure.
- */
-
-static int hgafb_pan_display(struct fb_var_screeninfo *var,
- struct fb_info *info)
-{
- if (var->vmode & FB_VMODE_YWRAP) {
- if (var->yoffset >= info->var.yres_virtual ||
- var->xoffset)
- return -EINVAL;
- } else {
- if (var->xoffset + info->var.xres > info->var.xres_virtual
- || var->yoffset + info->var.yres > info->var.yres_virtual
- || var->yoffset % 8)
- return -EINVAL;
- }
-
- hga_pan(var->xoffset, var->yoffset);
- return 0;
-}
-
-/**
- * hgafb_blank - (un)blank the screen
- * @blank_mode:blanking method to use
- * @info:unused
- *
- * Blank the screen if blank_mode != 0, else unblank.
- * Implements VESA suspend and powerdown modes on hardware that supports
- * disabling hsync/vsync:
- * @blank_mode == 2 means suspend vsync,
- * @blank_mode == 3 means suspend hsync,
- * @blank_mode == 4 means powerdown.
- *
- * Returns: %0
- */
-
-static int hgafb_blank(int blank_mode, struct fb_info *info)
-{
- hga_blank(blank_mode);
- return 0;
-}
-
-/*
- * Accel functions
- */
-static void hgafb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
-{
- u_int rows, y;
- u8 __iomem *dest;
-
- y = rect->dy;
-
- for (rows = rect->height; rows--; y++) {
- dest = rowaddr(info, y) + (rect->dx >> 3);
- switch (rect->rop) {
- case ROP_COPY:
- memset_io(dest, rect->color, (rect->width >> 3));
- break;
- case ROP_XOR:
- fb_writeb(~(fb_readb(dest)), dest);
- break;
- }
- }
-}
-
-static void hgafb_copyarea(struct fb_info *info, const struct fb_copyarea *area)
-{
- u_int rows, y1, y2;
- u8 __iomem *src;
- u8 __iomem *dest;
-
- if (area->dy <= area->sy) {
- y1 = area->sy;
- y2 = area->dy;
-
- for (rows = area->height; rows--; ) {
- src = rowaddr(info, y1) + (area->sx >> 3);
- dest = rowaddr(info, y2) + (area->dx >> 3);
- memmove(dest, src, (area->width >> 3));
- y1++;
- y2++;
- }
- } else {
- y1 = area->sy + area->height - 1;
- y2 = area->dy + area->height - 1;
-
- for (rows = area->height; rows--;) {
- src = rowaddr(info, y1) + (area->sx >> 3);
- dest = rowaddr(info, y2) + (area->dx >> 3);
- memmove(dest, src, (area->width >> 3));
- y1--;
- y2--;
- }
- }
-}
-
-static void hgafb_imageblit(struct fb_info *info, const struct fb_image *image)
-{
- u8 __iomem *dest;
- u8 *cdat = (u8 *) image->data;
- u_int rows, y = image->dy;
- u_int x;
- u8 d;
-
- for (rows = image->height; rows--; y++) {
- for (x = 0; x < image->width; x+= 8) {
- d = *cdat++;
- dest = rowaddr(info, y) + ((image->dx + x)>> 3);
- fb_writeb(d, dest);
- }
- }
-}
-
-static const struct fb_ops hgafb_ops = {
- .owner = THIS_MODULE,
- .fb_open = hgafb_open,
- .fb_release = hgafb_release,
- __FB_DEFAULT_IOMEM_OPS_RDWR,
- .fb_setcolreg = hgafb_setcolreg,
- .fb_pan_display = hgafb_pan_display,
- .fb_blank = hgafb_blank,
- .fb_fillrect = hgafb_fillrect,
- .fb_copyarea = hgafb_copyarea,
- .fb_imageblit = hgafb_imageblit,
- __FB_DEFAULT_IOMEM_OPS_MMAP,
-};
-
-/* ------------------------------------------------------------------------- *
- *
- * Functions in fb_info
- *
- * ------------------------------------------------------------------------- */
-
-/* ------------------------------------------------------------------------- */
-
- /*
- * Initialization
- */
-
-static int hgafb_probe(struct platform_device *pdev)
-{
- struct fb_info *info;
- int ret;
-
- ret = hga_card_detect(pdev);
- if (ret)
- return ret;
-
- printk(KERN_INFO "hgafb: %s with %ldK of memory detected.\n",
- hga_type_name, hga_vram_len/1024);
-
- info = framebuffer_alloc(0, &pdev->dev);
- if (!info) {
- iounmap(hga_vram);
- return -ENOMEM;
- }
-
- hga_fix.smem_start = (unsigned long)hga_vram;
- hga_fix.smem_len = hga_vram_len;
-
- info->flags = FBINFO_HWACCEL_YPAN;
- info->var = hga_default_var;
- info->fix = hga_fix;
- info->monspecs.hfmin = 0;
- info->monspecs.hfmax = 0;
- info->monspecs.vfmin = 10000;
- info->monspecs.vfmax = 10000;
- info->monspecs.dpms = 0;
- info->fbops = &hgafb_ops;
- info->screen_base = hga_vram;
-
- if (register_framebuffer(info) < 0) {
- framebuffer_release(info);
- iounmap(hga_vram);
- return -EINVAL;
- }
-
- fb_info(info, "%s frame buffer device\n", info->fix.id);
- platform_set_drvdata(pdev, info);
- return 0;
-}
-
-static void hgafb_remove(struct platform_device *pdev)
-{
- struct fb_info *info = platform_get_drvdata(pdev);
-
- hga_txt_mode();
- hga_clear_screen();
-
- if (info) {
- unregister_framebuffer(info);
- framebuffer_release(info);
- }
-
- iounmap(hga_vram);
-
- if (release_io_ports)
- release_region(0x3b0, 12);
-
- if (release_io_port)
- release_region(0x3bf, 1);
-}
-
-static struct platform_driver hgafb_driver = {
- .probe = hgafb_probe,
- .remove = hgafb_remove,
- .driver = {
- .name = "hgafb",
- },
-};
-
-static struct platform_device *hgafb_device;
-
-static int __init hgafb_init(void)
-{
- int ret;
-
- if (fb_get_options("hgafb", NULL))
- return -ENODEV;
-
- ret = platform_driver_register(&hgafb_driver);
-
- if (!ret) {
- hgafb_device = platform_device_register_simple("hgafb", 0, NULL, 0);
-
- if (IS_ERR(hgafb_device)) {
- platform_driver_unregister(&hgafb_driver);
- ret = PTR_ERR(hgafb_device);
- }
- }
-
- return ret;
-}
-
-static void __exit hgafb_exit(void)
-{
- platform_device_unregister(hgafb_device);
- platform_driver_unregister(&hgafb_driver);
-}
-
-/* -------------------------------------------------------------------------
- *
- * Modularization
- *
- * ------------------------------------------------------------------------- */
-
-MODULE_AUTHOR("Ferenc Bakonyi <fero@drama.obuda.kando.hu>");
-MODULE_DESCRIPTION("FBDev driver for Hercules Graphics Adaptor");
-MODULE_LICENSE("GPL");
-
-module_param(nologo, bool, 0);
-MODULE_PARM_DESC(nologo, "Disables startup logo if != 0 (default=0)");
-module_init(hgafb_init);
-module_exit(hgafb_exit);
--
2.43.0
^ permalink raw reply related
* Re: [PATCH] video: fbdev: remove Hercules monochrome ISA graphics adapter driver
From: Ethan Nelson-Moore @ 2026-05-03 5:45 UTC (permalink / raw)
To: linux-fbdev
Cc: Ferenc Bakonyi, Helge Deller, Jakub Kicinski, Andrew Morton,
Namjae Jeon, Hisam Mehboob, Martin Kepplinger-Novaković,
Diego Viola, Thomas Zimmermann, Wei Liu, Prasanna Kumar T S M,
robgithub, Hardik Phalet
In-Reply-To: <20260503045653.33522-1-enelsonmoore@gmail.com>
On Sat, May 2, 2026 at 9:57 PM Ethan Nelson-Moore
<enelsonmoore@gmail.com> wrote:
> The hgafb supports graphics adapters compatible with the Hercules
The hgafb *driver*, of course. Oops. Would whoever merges this please
fix that up?
Ethan
^ permalink raw reply
* Re: [PATCH] sm750fb: fix spelling typo in comment
From: Greg Kroah-Hartman @ 2026-05-04 9:32 UTC (permalink / raw)
To: auth
Cc: Sudip Mukherjee, Teddy Wang,
open list:STAGING - SILICON MOTION SM750 FRAME BUFFER DRIVER,
open list:STAGING SUBSYSTEM, open list
In-Reply-To: <20260429001557.71737-1-skunkolee@gmail.com>
On Tue, Apr 28, 2026 at 06:15:56PM -0600, auth wrote:
> Fixed suspected typo in comment ("programe" -> "program").
>
> Signed-off-by: auth <skunkolee@gmail.com>
> ---
> drivers/staging/sm750fb/ddk750_mode.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/staging/sm750fb/ddk750_mode.c b/drivers/staging/sm750fb/ddk750_mode.c
> index 7163232c0701..6363a66d5570 100644
> --- a/drivers/staging/sm750fb/ddk750_mode.c
> +++ b/drivers/staging/sm750fb/ddk750_mode.c
> @@ -82,7 +82,7 @@ static void program_mode_registers(struct mode_parameter *mode_param,
> unsigned int tmp, reg;
>
> if (pll->clock_type == SECONDARY_PLL) {
> - /* programe secondary pixel clock */
> + /* program secondary pixel clock */
> poke32(CRT_PLL_CTRL, sm750_format_pll_reg(pll));
>
> tmp = ((mode_param->horizontal_total - 1) <<
> --
> 2.54.0
>
Hi,
This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him
a patch that has triggered this response. He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created. Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.
You are receiving this message because of the following common error(s)
as indicated below:
- It looks like you did not use your "real" name for the patch on either
the Signed-off-by: line, or the From: line (both of which have to
match). Please read the kernel file,
Documentation/process/submitting-patches.rst for how to do this
correctly.
If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
from other developers.
thanks,
greg k-h's patch email bot
^ permalink raw reply
* Re: [PATCH 1/3] staging: sm750fb: add const qualifier to string pointer arrays
From: Greg KH @ 2026-05-04 9:32 UTC (permalink / raw)
To: Francisco Maestre
Cc: sudipm.mukherjee, teddy.wang, linux-fbdev, linux-staging,
linux-kernel
In-Reply-To: <20260503004134.66693-1-francisco@maestretorreblanca.com>
On Sat, May 02, 2026 at 07:41:34PM -0500, Francisco Maestre wrote:
> Add 'const' qualifier to 'g_fbmode' and 'g_def_fbmode' pointer
> declarations to make them 'static const char * const', as the
> pointers themselves are not modified after initialization.
>
> This fixes the following checkpatch.pl warning:
> WARNING: static const char * array should probably be
> static const char * const
>
> Signed-off-by: Francisco Maestre <francisco@maestretorreblanca.com>
> ---
> drivers/staging/sm750fb/sm750.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/sm750fb/sm750.c b/drivers/staging/sm750fb/sm750.c
> index 62f6e0cdff4d..dc9653ed2108 100644
> --- a/drivers/staging/sm750fb/sm750.c
> +++ b/drivers/staging/sm750fb/sm750.c
> @@ -33,8 +33,8 @@
> static int g_hwcursor = 1;
> static int g_noaccel;
> static int g_nomtrr;
> -static const char *g_fbmode[] = {NULL, NULL};
> -static const char *g_def_fbmode = "1024x768-32@60";
> +static const char * const g_fbmode[] = {NULL, NULL};
> +static const char * const g_def_fbmode = "1024x768-32@60";
> static char *g_settings;
> static int g_dualview;
> static char *g_option;
> --
> 2.50.1 (Apple Git-155)
>
>
These are not all threaded together, can you please resend them all as a
correct patch series?
thanks,
greg k-h
^ permalink raw reply
* [PATCH 7.0 162/307] fbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_info
From: Greg Kroah-Hartman @ 2026-05-04 13:50 UTC (permalink / raw)
To: stable
Cc: Greg Kroah-Hartman, patches, Thomas Zimmermann, Helge Deller,
linux-fbdev, dri-devel
In-Reply-To: <20260504135142.814938198@linuxfoundation.org>
7.0-stable review patch. If anyone has any objections, please let me know.
------------------
From: Thomas Zimmermann <tzimmermann@suse.de>
commit 9ded47ad003f09a94b6a710b5c47f4aa5ceb7429 upstream.
Hold state of deferred I/O in struct fb_deferred_io_state. Allocate an
instance as part of initializing deferred I/O and remove it only after
the final mapping has been closed. If the fb_info and the contained
deferred I/O meanwhile goes away, clear struct fb_deferred_io_state.info
to invalidate the mapping. Any access will then result in a SIGBUS
signal.
Fixes a long-standing problem, where a device hot-unplug happens while
user space still has an active mapping of the graphics memory. The hot-
unplug frees the instance of struct fb_info. Accessing the memory will
operate on undefined state.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 60b59beafba8 ("fbdev: mm: Deferred IO support")
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: stable@vger.kernel.org # v2.6.22+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/video/fbdev/core/fb_defio.c | 178 ++++++++++++++++++++++++++++--------
include/linux/fb.h | 4
2 files changed, 145 insertions(+), 37 deletions(-)
--- a/drivers/video/fbdev/core/fb_defio.c
+++ b/drivers/video/fbdev/core/fb_defio.c
@@ -24,6 +24,75 @@
#include <linux/rmap.h>
#include <linux/pagemap.h>
+/*
+ * struct fb_deferred_io_state
+ */
+
+struct fb_deferred_io_state {
+ struct kref ref;
+
+ struct mutex lock; /* mutex that protects the pageref list */
+ /* fields protected by lock */
+ struct fb_info *info;
+};
+
+static struct fb_deferred_io_state *fb_deferred_io_state_alloc(void)
+{
+ struct fb_deferred_io_state *fbdefio_state;
+
+ fbdefio_state = kzalloc_obj(*fbdefio_state);
+ if (!fbdefio_state)
+ return NULL;
+
+ kref_init(&fbdefio_state->ref);
+ mutex_init(&fbdefio_state->lock);
+
+ return fbdefio_state;
+}
+
+static void fb_deferred_io_state_release(struct fb_deferred_io_state *fbdefio_state)
+{
+ mutex_destroy(&fbdefio_state->lock);
+
+ kfree(fbdefio_state);
+}
+
+static void fb_deferred_io_state_get(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_get(&fbdefio_state->ref);
+}
+
+static void __fb_deferred_io_state_release(struct kref *ref)
+{
+ struct fb_deferred_io_state *fbdefio_state =
+ container_of(ref, struct fb_deferred_io_state, ref);
+
+ fb_deferred_io_state_release(fbdefio_state);
+}
+
+static void fb_deferred_io_state_put(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_put(&fbdefio_state->ref, __fb_deferred_io_state_release);
+}
+
+/*
+ * struct vm_operations_struct
+ */
+
+static void fb_deferred_io_vm_open(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_get(fbdefio_state);
+}
+
+static void fb_deferred_io_vm_close(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_put(fbdefio_state);
+}
+
static struct page *fb_deferred_io_get_page(struct fb_info *info, unsigned long offs)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
@@ -121,25 +190,46 @@ static void fb_deferred_io_pageref_put(s
/* this is to find and return the vmalloc-ed fb pages */
static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
{
+ struct fb_info *info;
unsigned long offset;
struct page *page;
- struct fb_info *info = vmf->vma->vm_private_data;
+ vm_fault_t ret;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
+
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
offset = vmf->pgoff << PAGE_SHIFT;
- if (offset >= info->fix.smem_len)
- return VM_FAULT_SIGBUS;
+ if (offset >= info->fix.smem_len) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
page = fb_deferred_io_get_page(info, offset);
- if (!page)
- return VM_FAULT_SIGBUS;
+ if (!page) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
if (!vmf->vma->vm_file)
fb_err(info, "no mapping available\n");
BUG_ON(!info->fbdefio->mapping);
+ mutex_unlock(&fbdefio_state->lock);
+
vmf->page = page;
+
return 0;
+
+err_mutex_unlock:
+ mutex_unlock(&fbdefio_state->lock);
+ return ret;
}
int fb_deferred_io_fsync(struct file *file, loff_t start, loff_t end, int datasync)
@@ -166,15 +256,24 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_fsync);
* Adds a page to the dirty list. Call this from struct
* vm_operations_struct.page_mkwrite.
*/
-static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long offset,
- struct page *page)
+static vm_fault_t fb_deferred_io_track_page(struct fb_deferred_io_state *fbdefio_state,
+ unsigned long offset, struct page *page)
{
- struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_info *info;
+ struct fb_deferred_io *fbdefio;
struct fb_deferred_io_pageref *pageref;
vm_fault_t ret;
/* protect against the workqueue changing the page list */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
+
+ fbdefio = info->fbdefio;
pageref = fb_deferred_io_pageref_get(info, offset, page);
if (WARN_ON_ONCE(!pageref)) {
@@ -192,50 +291,38 @@ static vm_fault_t fb_deferred_io_track_p
*/
lock_page(pageref->page);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
/* come back after delay to process the deferred IO */
schedule_delayed_work(&info->deferred_work, fbdefio->delay);
return VM_FAULT_LOCKED;
err_mutex_unlock:
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
return ret;
}
-/*
- * fb_deferred_io_page_mkwrite - Mark a page as written for deferred I/O
- * @fb_info: The fbdev info structure
- * @vmf: The VM fault
- *
- * This is a callback we get when userspace first tries to
- * write to the page. We schedule a workqueue. That workqueue
- * will eventually mkclean the touched pages and execute the
- * deferred framebuffer IO. Then if userspace touches a page
- * again, we repeat the same scheme.
- *
- * Returns:
- * VM_FAULT_LOCKED on success, or a VM_FAULT error otherwise.
- */
-static vm_fault_t fb_deferred_io_page_mkwrite(struct fb_info *info, struct vm_fault *vmf)
+static vm_fault_t fb_deferred_io_page_mkwrite(struct fb_deferred_io_state *fbdefio_state,
+ struct vm_fault *vmf)
{
unsigned long offset = vmf->pgoff << PAGE_SHIFT;
struct page *page = vmf->page;
file_update_time(vmf->vma->vm_file);
- return fb_deferred_io_track_page(info, offset, page);
+ return fb_deferred_io_track_page(fbdefio_state, offset, page);
}
-/* vm_ops->page_mkwrite handler */
static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
{
- struct fb_info *info = vmf->vma->vm_private_data;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
- return fb_deferred_io_page_mkwrite(info, vmf);
+ return fb_deferred_io_page_mkwrite(fbdefio_state, vmf);
}
static const struct vm_operations_struct fb_deferred_io_vm_ops = {
+ .open = fb_deferred_io_vm_open,
+ .close = fb_deferred_io_vm_close,
.fault = fb_deferred_io_fault,
.page_mkwrite = fb_deferred_io_mkwrite,
};
@@ -252,7 +339,10 @@ int fb_deferred_io_mmap(struct fb_info *
vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
if (!(info->flags & FBINFO_VIRTFB))
vm_flags_set(vma, VM_IO);
- vma->vm_private_data = info;
+ vma->vm_private_data = info->fbdefio_state;
+
+ fb_deferred_io_state_get(info->fbdefio_state); /* released in vma->vm_ops->close() */
+
return 0;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_mmap);
@@ -263,9 +353,10 @@ static void fb_deferred_io_work(struct w
struct fb_info *info = container_of(work, struct fb_info, deferred_work.work);
struct fb_deferred_io_pageref *pageref, *next;
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
/* here we wrprotect the page's mappings, then do all deferred IO. */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
#ifdef CONFIG_MMU
list_for_each_entry(pageref, &fbdefio->pagereflist, list) {
struct page *page = pageref->page;
@@ -283,12 +374,13 @@ static void fb_deferred_io_work(struct w
list_for_each_entry_safe(pageref, next, &fbdefio->pagereflist, list)
fb_deferred_io_pageref_put(pageref, info);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
}
int fb_deferred_io_init(struct fb_info *info)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
struct fb_deferred_io_pageref *pagerefs;
unsigned long npagerefs;
int ret;
@@ -298,7 +390,11 @@ int fb_deferred_io_init(struct fb_info *
if (WARN_ON(!info->fix.smem_len))
return -EINVAL;
- mutex_init(&fbdefio->lock);
+ fbdefio_state = fb_deferred_io_state_alloc();
+ if (!fbdefio_state)
+ return -ENOMEM;
+ fbdefio_state->info = info;
+
INIT_DELAYED_WORK(&info->deferred_work, fb_deferred_io_work);
INIT_LIST_HEAD(&fbdefio->pagereflist);
if (fbdefio->delay == 0) /* set a default of 1 s */
@@ -315,10 +411,12 @@ int fb_deferred_io_init(struct fb_info *
info->npagerefs = npagerefs;
info->pagerefs = pagerefs;
+ info->fbdefio_state = fbdefio_state;
+
return 0;
err:
- mutex_destroy(&fbdefio->lock);
+ fb_deferred_io_state_release(fbdefio_state);
return ret;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_init);
@@ -352,11 +450,19 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_release
void fb_deferred_io_cleanup(struct fb_info *info)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
fb_deferred_io_lastclose(info);
+ info->fbdefio_state = NULL;
+
+ mutex_lock(&fbdefio_state->lock);
+ fbdefio_state->info = NULL;
+ mutex_unlock(&fbdefio_state->lock);
+
+ fb_deferred_io_state_put(fbdefio_state);
+
kvfree(info->pagerefs);
- mutex_destroy(&fbdefio->lock);
fbdefio->mapping = NULL;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -218,13 +218,14 @@ struct fb_deferred_io {
unsigned long delay;
bool sort_pagereflist; /* sort pagelist by offset */
int open_count; /* number of opened files; protected by fb_info lock */
- struct mutex lock; /* mutex that protects the pageref list */
struct list_head pagereflist; /* list of pagerefs for touched pages */
struct address_space *mapping; /* page cache object for fb device */
/* callback */
struct page *(*get_page)(struct fb_info *info, unsigned long offset);
void (*deferred_io)(struct fb_info *info, struct list_head *pagelist);
};
+
+struct fb_deferred_io_state;
#endif
/*
@@ -487,6 +488,7 @@ struct fb_info {
unsigned long npagerefs;
struct fb_deferred_io_pageref *pagerefs;
struct fb_deferred_io *fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
#endif
const struct fb_ops *fbops;
^ permalink raw reply
* [PATCH 7.0 179/307] firmware: google: framebuffer: Do not unregister platform device
From: Greg Kroah-Hartman @ 2026-05-04 13:51 UTC (permalink / raw)
To: stable
Cc: Greg Kroah-Hartman, patches, Thomas Zimmermann, Tzung-Bi Shih,
Julius Werner, Javier Martinez Canillas, Hans de Goede,
linux-fbdev
In-Reply-To: <20260504135142.814938198@linuxfoundation.org>
7.0-stable review patch. If anyone has any objections, please let me know.
------------------
From: Thomas Zimmermann <tzimmermann@suse.de>
commit 5cd28bd28c8ce426b56ce4230dbd17537181d5ad upstream.
The native driver takes over the framebuffer aperture by removing the
system- framebuffer platform device. Afterwards the pointer in drvdata
is dangling. Remove the entire logic around drvdata and let the kernel's
aperture helpers handle this. The platform device depends on the native
hardware device instead of the coreboot device anyway.
When commit 851b4c14532d ("firmware: coreboot: Add coreboot framebuffer
driver") added the coreboot framebuffer code, the kernel did not support
device-based aperture management. Instead native driviers only removed
the conflicting fbdev device. At that point, unregistering the framebuffer
device most likely worked correctly. It was definitely broken after
commit d9702b2a2171 ("fbdev/simplefb: Do not use struct
fb_info.apertures"). So take this commit for the Fixes tag. Earlier
releases might work depending on the native hardware driver.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: d9702b2a2171 ("fbdev/simplefb: Do not use struct fb_info.apertures")
Acked-by: Tzung-Bi Shih <tzungbi@kernel.org>
Acked-by: Julius Werner <jwerner@chromium.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Hans de Goede <hansg@kernel.org>
Cc: linux-fbdev@vger.kernel.org
Cc: <stable@vger.kernel.org> # v6.3+
Link: https://patch.msgid.link/20260217155836.96267-2-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/firmware/google/framebuffer-coreboot.c | 10 ----------
1 file changed, 10 deletions(-)
--- a/drivers/firmware/google/framebuffer-coreboot.c
+++ b/drivers/firmware/google/framebuffer-coreboot.c
@@ -81,19 +81,10 @@ static int framebuffer_probe(struct core
sizeof(pdata));
if (IS_ERR(pdev))
pr_warn("coreboot: could not register framebuffer\n");
- else
- dev_set_drvdata(&dev->dev, pdev);
return PTR_ERR_OR_ZERO(pdev);
}
-static void framebuffer_remove(struct coreboot_device *dev)
-{
- struct platform_device *pdev = dev_get_drvdata(&dev->dev);
-
- platform_device_unregister(pdev);
-}
-
static const struct coreboot_device_id framebuffer_ids[] = {
{ .tag = CB_TAG_FRAMEBUFFER },
{ /* sentinel */ }
@@ -102,7 +93,6 @@ MODULE_DEVICE_TABLE(coreboot, framebuffe
static struct coreboot_driver framebuffer_driver = {
.probe = framebuffer_probe,
- .remove = framebuffer_remove,
.drv = {
.name = "framebuffer",
},
^ permalink raw reply
* [PATCH 6.18 151/275] firmware: google: framebuffer: Do not unregister platform device
From: Greg Kroah-Hartman @ 2026-05-04 13:51 UTC (permalink / raw)
To: stable
Cc: Greg Kroah-Hartman, patches, Thomas Zimmermann, Tzung-Bi Shih,
Julius Werner, Javier Martinez Canillas, Hans de Goede,
linux-fbdev
In-Reply-To: <20260504135142.929052779@linuxfoundation.org>
6.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Thomas Zimmermann <tzimmermann@suse.de>
commit 5cd28bd28c8ce426b56ce4230dbd17537181d5ad upstream.
The native driver takes over the framebuffer aperture by removing the
system- framebuffer platform device. Afterwards the pointer in drvdata
is dangling. Remove the entire logic around drvdata and let the kernel's
aperture helpers handle this. The platform device depends on the native
hardware device instead of the coreboot device anyway.
When commit 851b4c14532d ("firmware: coreboot: Add coreboot framebuffer
driver") added the coreboot framebuffer code, the kernel did not support
device-based aperture management. Instead native driviers only removed
the conflicting fbdev device. At that point, unregistering the framebuffer
device most likely worked correctly. It was definitely broken after
commit d9702b2a2171 ("fbdev/simplefb: Do not use struct
fb_info.apertures"). So take this commit for the Fixes tag. Earlier
releases might work depending on the native hardware driver.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: d9702b2a2171 ("fbdev/simplefb: Do not use struct fb_info.apertures")
Acked-by: Tzung-Bi Shih <tzungbi@kernel.org>
Acked-by: Julius Werner <jwerner@chromium.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Hans de Goede <hansg@kernel.org>
Cc: linux-fbdev@vger.kernel.org
Cc: <stable@vger.kernel.org> # v6.3+
Link: https://patch.msgid.link/20260217155836.96267-2-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/firmware/google/framebuffer-coreboot.c | 10 ----------
1 file changed, 10 deletions(-)
--- a/drivers/firmware/google/framebuffer-coreboot.c
+++ b/drivers/firmware/google/framebuffer-coreboot.c
@@ -81,19 +81,10 @@ static int framebuffer_probe(struct core
sizeof(pdata));
if (IS_ERR(pdev))
pr_warn("coreboot: could not register framebuffer\n");
- else
- dev_set_drvdata(&dev->dev, pdev);
return PTR_ERR_OR_ZERO(pdev);
}
-static void framebuffer_remove(struct coreboot_device *dev)
-{
- struct platform_device *pdev = dev_get_drvdata(&dev->dev);
-
- platform_device_unregister(pdev);
-}
-
static const struct coreboot_device_id framebuffer_ids[] = {
{ .tag = CB_TAG_FRAMEBUFFER },
{ /* sentinel */ }
@@ -102,7 +93,6 @@ MODULE_DEVICE_TABLE(coreboot, framebuffe
static struct coreboot_driver framebuffer_driver = {
.probe = framebuffer_probe,
- .remove = framebuffer_remove,
.drv = {
.name = "framebuffer",
},
^ permalink raw reply
* [PATCH 6.18.y] fbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_info
From: Sasha Levin @ 2026-05-04 14:19 UTC (permalink / raw)
To: stable; +Cc: Thomas Zimmermann, Helge Deller, linux-fbdev, dri-devel,
Sasha Levin
In-Reply-To: <2026050146-growl-viselike-2a67@gregkh>
From: Thomas Zimmermann <tzimmermann@suse.de>
[ Upstream commit 9ded47ad003f09a94b6a710b5c47f4aa5ceb7429 ]
Hold state of deferred I/O in struct fb_deferred_io_state. Allocate an
instance as part of initializing deferred I/O and remove it only after
the final mapping has been closed. If the fb_info and the contained
deferred I/O meanwhile goes away, clear struct fb_deferred_io_state.info
to invalidate the mapping. Any access will then result in a SIGBUS
signal.
Fixes a long-standing problem, where a device hot-unplug happens while
user space still has an active mapping of the graphics memory. The hot-
unplug frees the instance of struct fb_info. Accessing the memory will
operate on undefined state.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 60b59beafba8 ("fbdev: mm: Deferred IO support")
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: stable@vger.kernel.org # v2.6.22+
Signed-off-by: Helge Deller <deller@gmx.de>
[ replaced kzalloc_obj(*fbdefio_state) with kzalloc(sizeof(*fbdefio_state), GFP_KERNEL) ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/video/fbdev/core/fb_defio.c | 178 ++++++++++++++++++++++------
include/linux/fb.h | 4 +-
2 files changed, 145 insertions(+), 37 deletions(-)
diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c
index 8df2e51e33909..0b099a89a8234 100644
--- a/drivers/video/fbdev/core/fb_defio.c
+++ b/drivers/video/fbdev/core/fb_defio.c
@@ -24,6 +24,75 @@
#include <linux/rmap.h>
#include <linux/pagemap.h>
+/*
+ * struct fb_deferred_io_state
+ */
+
+struct fb_deferred_io_state {
+ struct kref ref;
+
+ struct mutex lock; /* mutex that protects the pageref list */
+ /* fields protected by lock */
+ struct fb_info *info;
+};
+
+static struct fb_deferred_io_state *fb_deferred_io_state_alloc(void)
+{
+ struct fb_deferred_io_state *fbdefio_state;
+
+ fbdefio_state = kzalloc(sizeof(*fbdefio_state), GFP_KERNEL);
+ if (!fbdefio_state)
+ return NULL;
+
+ kref_init(&fbdefio_state->ref);
+ mutex_init(&fbdefio_state->lock);
+
+ return fbdefio_state;
+}
+
+static void fb_deferred_io_state_release(struct fb_deferred_io_state *fbdefio_state)
+{
+ mutex_destroy(&fbdefio_state->lock);
+
+ kfree(fbdefio_state);
+}
+
+static void fb_deferred_io_state_get(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_get(&fbdefio_state->ref);
+}
+
+static void __fb_deferred_io_state_release(struct kref *ref)
+{
+ struct fb_deferred_io_state *fbdefio_state =
+ container_of(ref, struct fb_deferred_io_state, ref);
+
+ fb_deferred_io_state_release(fbdefio_state);
+}
+
+static void fb_deferred_io_state_put(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_put(&fbdefio_state->ref, __fb_deferred_io_state_release);
+}
+
+/*
+ * struct vm_operations_struct
+ */
+
+static void fb_deferred_io_vm_open(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_get(fbdefio_state);
+}
+
+static void fb_deferred_io_vm_close(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_put(fbdefio_state);
+}
+
static struct page *fb_deferred_io_get_page(struct fb_info *info, unsigned long offs)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
@@ -121,25 +190,46 @@ static void fb_deferred_io_pageref_put(struct fb_deferred_io_pageref *pageref,
/* this is to find and return the vmalloc-ed fb pages */
static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
{
+ struct fb_info *info;
unsigned long offset;
struct page *page;
- struct fb_info *info = vmf->vma->vm_private_data;
+ vm_fault_t ret;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
+
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
offset = vmf->pgoff << PAGE_SHIFT;
- if (offset >= info->fix.smem_len)
- return VM_FAULT_SIGBUS;
+ if (offset >= info->fix.smem_len) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
page = fb_deferred_io_get_page(info, offset);
- if (!page)
- return VM_FAULT_SIGBUS;
+ if (!page) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
if (!vmf->vma->vm_file)
fb_err(info, "no mapping available\n");
BUG_ON(!info->fbdefio->mapping);
+ mutex_unlock(&fbdefio_state->lock);
+
vmf->page = page;
+
return 0;
+
+err_mutex_unlock:
+ mutex_unlock(&fbdefio_state->lock);
+ return ret;
}
int fb_deferred_io_fsync(struct file *file, loff_t start, loff_t end, int datasync)
@@ -166,15 +256,24 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_fsync);
* Adds a page to the dirty list. Call this from struct
* vm_operations_struct.page_mkwrite.
*/
-static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long offset,
- struct page *page)
+static vm_fault_t fb_deferred_io_track_page(struct fb_deferred_io_state *fbdefio_state,
+ unsigned long offset, struct page *page)
{
- struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_info *info;
+ struct fb_deferred_io *fbdefio;
struct fb_deferred_io_pageref *pageref;
vm_fault_t ret;
/* protect against the workqueue changing the page list */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
+
+ fbdefio = info->fbdefio;
pageref = fb_deferred_io_pageref_get(info, offset, page);
if (WARN_ON_ONCE(!pageref)) {
@@ -192,50 +291,38 @@ static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long
*/
lock_page(pageref->page);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
/* come back after delay to process the deferred IO */
schedule_delayed_work(&info->deferred_work, fbdefio->delay);
return VM_FAULT_LOCKED;
err_mutex_unlock:
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
return ret;
}
-/*
- * fb_deferred_io_page_mkwrite - Mark a page as written for deferred I/O
- * @fb_info: The fbdev info structure
- * @vmf: The VM fault
- *
- * This is a callback we get when userspace first tries to
- * write to the page. We schedule a workqueue. That workqueue
- * will eventually mkclean the touched pages and execute the
- * deferred framebuffer IO. Then if userspace touches a page
- * again, we repeat the same scheme.
- *
- * Returns:
- * VM_FAULT_LOCKED on success, or a VM_FAULT error otherwise.
- */
-static vm_fault_t fb_deferred_io_page_mkwrite(struct fb_info *info, struct vm_fault *vmf)
+static vm_fault_t fb_deferred_io_page_mkwrite(struct fb_deferred_io_state *fbdefio_state,
+ struct vm_fault *vmf)
{
unsigned long offset = vmf->pgoff << PAGE_SHIFT;
struct page *page = vmf->page;
file_update_time(vmf->vma->vm_file);
- return fb_deferred_io_track_page(info, offset, page);
+ return fb_deferred_io_track_page(fbdefio_state, offset, page);
}
-/* vm_ops->page_mkwrite handler */
static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
{
- struct fb_info *info = vmf->vma->vm_private_data;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
- return fb_deferred_io_page_mkwrite(info, vmf);
+ return fb_deferred_io_page_mkwrite(fbdefio_state, vmf);
}
static const struct vm_operations_struct fb_deferred_io_vm_ops = {
+ .open = fb_deferred_io_vm_open,
+ .close = fb_deferred_io_vm_close,
.fault = fb_deferred_io_fault,
.page_mkwrite = fb_deferred_io_mkwrite,
};
@@ -252,7 +339,10 @@ int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma)
vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
if (!(info->flags & FBINFO_VIRTFB))
vm_flags_set(vma, VM_IO);
- vma->vm_private_data = info;
+ vma->vm_private_data = info->fbdefio_state;
+
+ fb_deferred_io_state_get(info->fbdefio_state); /* released in vma->vm_ops->close() */
+
return 0;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_mmap);
@@ -263,9 +353,10 @@ static void fb_deferred_io_work(struct work_struct *work)
struct fb_info *info = container_of(work, struct fb_info, deferred_work.work);
struct fb_deferred_io_pageref *pageref, *next;
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
/* here we wrprotect the page's mappings, then do all deferred IO. */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
#ifdef CONFIG_MMU
list_for_each_entry(pageref, &fbdefio->pagereflist, list) {
struct page *page = pageref->page;
@@ -283,12 +374,13 @@ static void fb_deferred_io_work(struct work_struct *work)
list_for_each_entry_safe(pageref, next, &fbdefio->pagereflist, list)
fb_deferred_io_pageref_put(pageref, info);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
}
int fb_deferred_io_init(struct fb_info *info)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
struct fb_deferred_io_pageref *pagerefs;
unsigned long npagerefs;
int ret;
@@ -298,7 +390,11 @@ int fb_deferred_io_init(struct fb_info *info)
if (WARN_ON(!info->fix.smem_len))
return -EINVAL;
- mutex_init(&fbdefio->lock);
+ fbdefio_state = fb_deferred_io_state_alloc();
+ if (!fbdefio_state)
+ return -ENOMEM;
+ fbdefio_state->info = info;
+
INIT_DELAYED_WORK(&info->deferred_work, fb_deferred_io_work);
INIT_LIST_HEAD(&fbdefio->pagereflist);
if (fbdefio->delay == 0) /* set a default of 1 s */
@@ -315,10 +411,12 @@ int fb_deferred_io_init(struct fb_info *info)
info->npagerefs = npagerefs;
info->pagerefs = pagerefs;
+ info->fbdefio_state = fbdefio_state;
+
return 0;
err:
- mutex_destroy(&fbdefio->lock);
+ fb_deferred_io_state_release(fbdefio_state);
return ret;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_init);
@@ -352,11 +450,19 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_release);
void fb_deferred_io_cleanup(struct fb_info *info)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
fb_deferred_io_lastclose(info);
+ info->fbdefio_state = NULL;
+
+ mutex_lock(&fbdefio_state->lock);
+ fbdefio_state->info = NULL;
+ mutex_unlock(&fbdefio_state->lock);
+
+ fb_deferred_io_state_put(fbdefio_state);
+
kvfree(info->pagerefs);
- mutex_destroy(&fbdefio->lock);
fbdefio->mapping = NULL;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index c3302d5135466..da2fdabd18cb3 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -217,13 +217,14 @@ struct fb_deferred_io {
unsigned long delay;
bool sort_pagereflist; /* sort pagelist by offset */
int open_count; /* number of opened files; protected by fb_info lock */
- struct mutex lock; /* mutex that protects the pageref list */
struct list_head pagereflist; /* list of pagerefs for touched pages */
struct address_space *mapping; /* page cache object for fb device */
/* callback */
struct page *(*get_page)(struct fb_info *info, unsigned long offset);
void (*deferred_io)(struct fb_info *info, struct list_head *pagelist);
};
+
+struct fb_deferred_io_state;
#endif
/*
@@ -490,6 +491,7 @@ struct fb_info {
unsigned long npagerefs;
struct fb_deferred_io_pageref *pagerefs;
struct fb_deferred_io *fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
#endif
const struct fb_ops *fbops;
--
2.53.0
^ permalink raw reply related
* [PATCH 6.12 107/215] firmware: google: framebuffer: Do not unregister platform device
From: Greg Kroah-Hartman @ 2026-05-04 13:52 UTC (permalink / raw)
To: stable
Cc: Greg Kroah-Hartman, patches, Thomas Zimmermann, Tzung-Bi Shih,
Julius Werner, Javier Martinez Canillas, Hans de Goede,
linux-fbdev
In-Reply-To: <20260504135130.169210693@linuxfoundation.org>
6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Thomas Zimmermann <tzimmermann@suse.de>
commit 5cd28bd28c8ce426b56ce4230dbd17537181d5ad upstream.
The native driver takes over the framebuffer aperture by removing the
system- framebuffer platform device. Afterwards the pointer in drvdata
is dangling. Remove the entire logic around drvdata and let the kernel's
aperture helpers handle this. The platform device depends on the native
hardware device instead of the coreboot device anyway.
When commit 851b4c14532d ("firmware: coreboot: Add coreboot framebuffer
driver") added the coreboot framebuffer code, the kernel did not support
device-based aperture management. Instead native driviers only removed
the conflicting fbdev device. At that point, unregistering the framebuffer
device most likely worked correctly. It was definitely broken after
commit d9702b2a2171 ("fbdev/simplefb: Do not use struct
fb_info.apertures"). So take this commit for the Fixes tag. Earlier
releases might work depending on the native hardware driver.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: d9702b2a2171 ("fbdev/simplefb: Do not use struct fb_info.apertures")
Acked-by: Tzung-Bi Shih <tzungbi@kernel.org>
Acked-by: Julius Werner <jwerner@chromium.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Hans de Goede <hansg@kernel.org>
Cc: linux-fbdev@vger.kernel.org
Cc: <stable@vger.kernel.org> # v6.3+
Link: https://patch.msgid.link/20260217155836.96267-2-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/firmware/google/framebuffer-coreboot.c | 10 ----------
1 file changed, 10 deletions(-)
--- a/drivers/firmware/google/framebuffer-coreboot.c
+++ b/drivers/firmware/google/framebuffer-coreboot.c
@@ -67,19 +67,10 @@ static int framebuffer_probe(struct core
sizeof(pdata));
if (IS_ERR(pdev))
pr_warn("coreboot: could not register framebuffer\n");
- else
- dev_set_drvdata(&dev->dev, pdev);
return PTR_ERR_OR_ZERO(pdev);
}
-static void framebuffer_remove(struct coreboot_device *dev)
-{
- struct platform_device *pdev = dev_get_drvdata(&dev->dev);
-
- platform_device_unregister(pdev);
-}
-
static const struct coreboot_device_id framebuffer_ids[] = {
{ .tag = CB_TAG_FRAMEBUFFER },
{ /* sentinel */ }
@@ -88,7 +79,6 @@ MODULE_DEVICE_TABLE(coreboot, framebuffe
static struct coreboot_driver framebuffer_driver = {
.probe = framebuffer_probe,
- .remove = framebuffer_remove,
.drv = {
.name = "framebuffer",
},
^ permalink raw reply
* Re: [PATCH v2] staging: sm750fb: add const qualifier to string pointer arrays
From: Greg KH @ 2026-05-04 14:55 UTC (permalink / raw)
To: Francisco Maestre
Cc: sudipm.mukherjee, teddy.wang, linux-fbdev, linux-staging,
linux-kernel
In-Reply-To: <20260503005744.68974-1-francisco@maestretorreblanca.com>
On Sat, May 02, 2026 at 07:57:44PM -0500, Francisco Maestre wrote:
> Add 'const' qualifier to 'g_fbmode' and 'g_def_fbmode' pointer
> declarations to make them 'static const char * const', as the
> pointers themselves are not modified after initialization.
>
> This fixes the following checkpatch.pl warning:
> WARNING: static const char * array should probably be
> static const char * const
>
> Signed-off-by: Francisco Maestre <francisco@maestretorreblanca.com>
> ---
> v2: Resend as individual patch, not part of an unrelated series.
> drivers/staging/sm750fb/sm750.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/sm750fb/sm750.c b/drivers/staging/sm750fb/sm750.c
> index 62f6e0cdff4d..dc9653ed2108 100644
> --- a/drivers/staging/sm750fb/sm750.c
> +++ b/drivers/staging/sm750fb/sm750.c
> @@ -33,8 +33,8 @@
> static int g_hwcursor = 1;
> static int g_noaccel;
> static int g_nomtrr;
> -static const char *g_fbmode[] = {NULL, NULL};
> -static const char *g_def_fbmode = "1024x768-32@60";
> +static const char * const g_fbmode[] = {NULL, NULL};
> +static const char * const g_def_fbmode = "1024x768-32@60";
> static char *g_settings;
> static int g_dualview;
> static char *g_option;
> --
> 2.50.1 (Apple Git-155)
>
>
Any reason why you did not test build this patch? Always do so so that
you don't get grumpy maintainers asking why you didn't test build your
patch :)
thanks,
greg k-h
^ permalink raw reply
* [PATCH] staging: sm750fb: remove unnecessary initializations
From: Ahmet Sezgin Duran @ 2026-05-04 20:46 UTC (permalink / raw)
To: gregkh; +Cc: linux-fbdev, linux-staging, linux-kernel, Ahmet Sezgin Duran
Remove two instances of `ret = 0` initializations since the variable
is overridden unconditionally before being used.
Signed-off-by: Ahmet Sezgin Duran <ahmet@sezginduran.net>
---
drivers/staging/sm750fb/sm750_hw.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/drivers/staging/sm750fb/sm750_hw.c b/drivers/staging/sm750fb/sm750_hw.c
index beef05ded98d..780fe6c391d3 100644
--- a/drivers/staging/sm750fb/sm750_hw.c
+++ b/drivers/staging/sm750fb/sm750_hw.c
@@ -29,8 +29,6 @@ int hw_sm750_map(struct sm750_dev *sm750_dev, struct pci_dev *pdev)
{
int ret;
- ret = 0;
-
sm750_dev->vidreg_start = pci_resource_start(pdev, 1);
sm750_dev->vidreg_size = SZ_2M;
@@ -243,7 +241,6 @@ int hw_sm750_crtc_set_mode(struct lynxfb_crtc *crtc,
struct sm750_dev *sm750_dev;
struct lynxfb_par *par;
- ret = 0;
par = container_of(crtc, struct lynxfb_par, crtc);
sm750_dev = par->dev;
--
2.54.0
^ permalink raw reply related
* [PATCH 6.12.y] fbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_info
From: Sasha Levin @ 2026-05-05 0:14 UTC (permalink / raw)
To: stable; +Cc: Thomas Zimmermann, Helge Deller, linux-fbdev, dri-devel,
Sasha Levin
In-Reply-To: <2026050115-morality-reseal-5c07@gregkh>
From: Thomas Zimmermann <tzimmermann@suse.de>
[ Upstream commit 9ded47ad003f09a94b6a710b5c47f4aa5ceb7429 ]
Hold state of deferred I/O in struct fb_deferred_io_state. Allocate an
instance as part of initializing deferred I/O and remove it only after
the final mapping has been closed. If the fb_info and the contained
deferred I/O meanwhile goes away, clear struct fb_deferred_io_state.info
to invalidate the mapping. Any access will then result in a SIGBUS
signal.
Fixes a long-standing problem, where a device hot-unplug happens while
user space still has an active mapping of the graphics memory. The hot-
unplug frees the instance of struct fb_info. Accessing the memory will
operate on undefined state.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 60b59beafba8 ("fbdev: mm: Deferred IO support")
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: stable@vger.kernel.org # v2.6.22+
Signed-off-by: Helge Deller <deller@gmx.de>
[ replaced `kzalloc_obj()` with `kzalloc(sizeof(*fbdefio_state), GFP_KERNEL)` ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/video/fbdev/core/fb_defio.c | 179 ++++++++++++++++++++++------
include/linux/fb.h | 4 +-
2 files changed, 145 insertions(+), 38 deletions(-)
diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c
index 65363df8e81b5..e0a44298c248d 100644
--- a/drivers/video/fbdev/core/fb_defio.c
+++ b/drivers/video/fbdev/core/fb_defio.c
@@ -23,6 +23,75 @@
#include <linux/rmap.h>
#include <linux/pagemap.h>
+/*
+ * struct fb_deferred_io_state
+ */
+
+struct fb_deferred_io_state {
+ struct kref ref;
+
+ struct mutex lock; /* mutex that protects the pageref list */
+ /* fields protected by lock */
+ struct fb_info *info;
+};
+
+static struct fb_deferred_io_state *fb_deferred_io_state_alloc(void)
+{
+ struct fb_deferred_io_state *fbdefio_state;
+
+ fbdefio_state = kzalloc(sizeof(*fbdefio_state), GFP_KERNEL);
+ if (!fbdefio_state)
+ return NULL;
+
+ kref_init(&fbdefio_state->ref);
+ mutex_init(&fbdefio_state->lock);
+
+ return fbdefio_state;
+}
+
+static void fb_deferred_io_state_release(struct fb_deferred_io_state *fbdefio_state)
+{
+ mutex_destroy(&fbdefio_state->lock);
+
+ kfree(fbdefio_state);
+}
+
+static void fb_deferred_io_state_get(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_get(&fbdefio_state->ref);
+}
+
+static void __fb_deferred_io_state_release(struct kref *ref)
+{
+ struct fb_deferred_io_state *fbdefio_state =
+ container_of(ref, struct fb_deferred_io_state, ref);
+
+ fb_deferred_io_state_release(fbdefio_state);
+}
+
+static void fb_deferred_io_state_put(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_put(&fbdefio_state->ref, __fb_deferred_io_state_release);
+}
+
+/*
+ * struct vm_operations_struct
+ */
+
+static void fb_deferred_io_vm_open(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_get(fbdefio_state);
+}
+
+static void fb_deferred_io_vm_close(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_put(fbdefio_state);
+}
+
static struct page *fb_deferred_io_get_page(struct fb_info *info, unsigned long offs)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
@@ -128,17 +197,31 @@ static void fb_deferred_io_pageref_put(struct fb_deferred_io_pageref *pageref,
/* this is to find and return the vmalloc-ed fb pages */
static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
{
+ struct fb_info *info;
unsigned long offset;
struct page *page;
- struct fb_info *info = vmf->vma->vm_private_data;
+ vm_fault_t ret;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
+
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
offset = vmf->pgoff << PAGE_SHIFT;
- if (offset >= info->fix.smem_len)
- return VM_FAULT_SIGBUS;
+ if (offset >= info->fix.smem_len) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
page = fb_deferred_io_get_page(info, offset);
- if (!page)
- return VM_FAULT_SIGBUS;
+ if (!page) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
if (vmf->vma->vm_file)
page->mapping = vmf->vma->vm_file->f_mapping;
@@ -148,8 +231,15 @@ static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
BUG_ON(!page->mapping);
page->index = vmf->pgoff; /* for folio_mkclean() */
+ mutex_unlock(&fbdefio_state->lock);
+
vmf->page = page;
+
return 0;
+
+err_mutex_unlock:
+ mutex_unlock(&fbdefio_state->lock);
+ return ret;
}
int fb_deferred_io_fsync(struct file *file, loff_t start, loff_t end, int datasync)
@@ -176,15 +266,24 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_fsync);
* Adds a page to the dirty list. Call this from struct
* vm_operations_struct.page_mkwrite.
*/
-static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long offset,
- struct page *page)
+static vm_fault_t fb_deferred_io_track_page(struct fb_deferred_io_state *fbdefio_state,
+ unsigned long offset, struct page *page)
{
- struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_info *info;
+ struct fb_deferred_io *fbdefio;
struct fb_deferred_io_pageref *pageref;
vm_fault_t ret;
/* protect against the workqueue changing the page list */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
+
+ fbdefio = info->fbdefio;
pageref = fb_deferred_io_pageref_get(info, offset, page);
if (WARN_ON_ONCE(!pageref)) {
@@ -202,50 +301,38 @@ static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long
*/
lock_page(pageref->page);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
/* come back after delay to process the deferred IO */
schedule_delayed_work(&info->deferred_work, fbdefio->delay);
return VM_FAULT_LOCKED;
err_mutex_unlock:
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
return ret;
}
-/*
- * fb_deferred_io_page_mkwrite - Mark a page as written for deferred I/O
- * @fb_info: The fbdev info structure
- * @vmf: The VM fault
- *
- * This is a callback we get when userspace first tries to
- * write to the page. We schedule a workqueue. That workqueue
- * will eventually mkclean the touched pages and execute the
- * deferred framebuffer IO. Then if userspace touches a page
- * again, we repeat the same scheme.
- *
- * Returns:
- * VM_FAULT_LOCKED on success, or a VM_FAULT error otherwise.
- */
-static vm_fault_t fb_deferred_io_page_mkwrite(struct fb_info *info, struct vm_fault *vmf)
+static vm_fault_t fb_deferred_io_page_mkwrite(struct fb_deferred_io_state *fbdefio_state,
+ struct vm_fault *vmf)
{
unsigned long offset = vmf->pgoff << PAGE_SHIFT;
struct page *page = vmf->page;
file_update_time(vmf->vma->vm_file);
- return fb_deferred_io_track_page(info, offset, page);
+ return fb_deferred_io_track_page(fbdefio_state, offset, page);
}
-/* vm_ops->page_mkwrite handler */
static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
{
- struct fb_info *info = vmf->vma->vm_private_data;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
- return fb_deferred_io_page_mkwrite(info, vmf);
+ return fb_deferred_io_page_mkwrite(fbdefio_state, vmf);
}
static const struct vm_operations_struct fb_deferred_io_vm_ops = {
+ .open = fb_deferred_io_vm_open,
+ .close = fb_deferred_io_vm_close,
.fault = fb_deferred_io_fault,
.page_mkwrite = fb_deferred_io_mkwrite,
};
@@ -262,7 +349,10 @@ int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma)
vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
if (!(info->flags & FBINFO_VIRTFB))
vm_flags_set(vma, VM_IO);
- vma->vm_private_data = info;
+ vma->vm_private_data = info->fbdefio_state;
+
+ fb_deferred_io_state_get(info->fbdefio_state); /* released in vma->vm_ops->close() */
+
return 0;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_mmap);
@@ -273,9 +363,10 @@ static void fb_deferred_io_work(struct work_struct *work)
struct fb_info *info = container_of(work, struct fb_info, deferred_work.work);
struct fb_deferred_io_pageref *pageref, *next;
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
/* here we mkclean the pages, then do all deferred IO */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
list_for_each_entry(pageref, &fbdefio->pagereflist, list) {
struct folio *folio = page_folio(pageref->page);
@@ -291,12 +382,13 @@ static void fb_deferred_io_work(struct work_struct *work)
list_for_each_entry_safe(pageref, next, &fbdefio->pagereflist, list)
fb_deferred_io_pageref_put(pageref, info);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
}
int fb_deferred_io_init(struct fb_info *info)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
struct fb_deferred_io_pageref *pagerefs;
unsigned long npagerefs;
int ret;
@@ -306,7 +398,11 @@ int fb_deferred_io_init(struct fb_info *info)
if (WARN_ON(!info->fix.smem_len))
return -EINVAL;
- mutex_init(&fbdefio->lock);
+ fbdefio_state = fb_deferred_io_state_alloc();
+ if (!fbdefio_state)
+ return -ENOMEM;
+ fbdefio_state->info = info;
+
INIT_DELAYED_WORK(&info->deferred_work, fb_deferred_io_work);
INIT_LIST_HEAD(&fbdefio->pagereflist);
if (fbdefio->delay == 0) /* set a default of 1 s */
@@ -323,10 +419,12 @@ int fb_deferred_io_init(struct fb_info *info)
info->npagerefs = npagerefs;
info->pagerefs = pagerefs;
+ info->fbdefio_state = fbdefio_state;
+
return 0;
err:
- mutex_destroy(&fbdefio->lock);
+ fb_deferred_io_state_release(fbdefio_state);
return ret;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_init);
@@ -364,11 +462,18 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_release);
void fb_deferred_io_cleanup(struct fb_info *info)
{
- struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
fb_deferred_io_lastclose(info);
+ info->fbdefio_state = NULL;
+
+ mutex_lock(&fbdefio_state->lock);
+ fbdefio_state->info = NULL;
+ mutex_unlock(&fbdefio_state->lock);
+
+ fb_deferred_io_state_put(fbdefio_state);
+
kvfree(info->pagerefs);
- mutex_destroy(&fbdefio->lock);
}
EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 267b59ead4321..d87d6547c6e41 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -222,12 +222,13 @@ struct fb_deferred_io {
unsigned long delay;
bool sort_pagereflist; /* sort pagelist by offset */
int open_count; /* number of opened files; protected by fb_info lock */
- struct mutex lock; /* mutex that protects the pageref list */
struct list_head pagereflist; /* list of pagerefs for touched pages */
/* callback */
struct page *(*get_page)(struct fb_info *info, unsigned long offset);
void (*deferred_io)(struct fb_info *info, struct list_head *pagelist);
};
+
+struct fb_deferred_io_state;
#endif
/*
@@ -485,6 +486,7 @@ struct fb_info {
unsigned long npagerefs;
struct fb_deferred_io_pageref *pagerefs;
struct fb_deferred_io *fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
#endif
const struct fb_ops *fbops;
--
2.53.0
^ permalink raw reply related
* Re: [PATCH v1] fbdev: savage: fix probe-path EDID cleanup leaks
From: 최유호 @ 2026-05-05 1:35 UTC (permalink / raw)
To: Antonino Daplas, Helge Deller, linux-fbdev
Cc: dri-devel, linux-kernel, Myeonghun Pak, Ijae Kim, Taegyu Kim
In-Reply-To: <20260420051926.28276-1-dbgh9129@gmail.com>
Dear Antonino and Helge,
I am sending a gentle ping on this patch. Please let me know if you
have any feedback or if any changes are needed.
Best regards,
Yuho
On Mon, 20 Apr 2026 at 01:19, Yuho Choi <dbgh9129@gmail.com> wrote:
>
> When CONFIG_FB_SAVAGE_I2C is enabled, savagefb_probe() can build both an
> EDID-derived monspecs.modedb and a modelist from it before later
> failing.
>
> The normal success path frees monspecs.modedb after the initial mode
> selection, but the probe error path only deletes the I2C busses and
> misses the EDID-derived allocations.
>
> Free both the modelist and monspecs.modedb on the failed: unwind path.
>
> Co-developed-by: Myeonghun Pak <mhun512@gmail.com>
> Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
> Co-developed-by: Ijae Kim <ae878000@gmail.com>
> Signed-off-by: Ijae Kim <ae878000@gmail.com>
> Co-developed-by: Taegyu Kim <tmk5904@psu.edu>
> Signed-off-by: Taegyu Kim <tmk5904@psu.edu>
> Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
> ---
> drivers/video/fbdev/savage/savagefb_driver.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/video/fbdev/savage/savagefb_driver.c b/drivers/video/fbdev/savage/savagefb_driver.c
> index ac41f8f37589f..c2f79357c8da0 100644
> --- a/drivers/video/fbdev/savage/savagefb_driver.c
> +++ b/drivers/video/fbdev/savage/savagefb_driver.c
> @@ -2322,6 +2322,8 @@ static int savagefb_probe(struct pci_dev *dev, const struct pci_device_id *id)
> failed:
> #ifdef CONFIG_FB_SAVAGE_I2C
> savagefb_delete_i2c_busses(info);
> + fb_destroy_modelist(&info->modelist);
> + fb_destroy_modedb(info->monspecs.modedb);
> #endif
> fb_alloc_cmap(&info->cmap, 0, 0);
> savage_unmap_video(info);
> --
> 2.50.1 (Apple Git-155)
>
^ permalink raw reply
* [PATCH v1] fbdev: savage: fix probe-path EDID cleanup leaks
From: dbgh9129 @ 2026-05-05 1:35 UTC (permalink / raw)
To: adaplas, deller, linux-fbdev
Cc: dri-devel, linux-kernel, mhun512, ae878000, tmk5904, dbgh9129
In-Reply-To: <20260420051926.28276-1-dbgh9129@gmail.com>
Hi Antonino and Helge,
I am sending a gentle ping on this patch. Please let me know if you
have any feedback or if any changes are needed.
Best regards,
Yuho Choi
^ permalink raw reply
* [PATCH v1] fbdev/offb: fix PCI device reference leak on probe failure
From: dbgh9129 @ 2026-05-05 1:39 UTC (permalink / raw)
To: deller, Jason, linux-fbdev
Cc: dri-devel, linux-kernel, mhun512, ae878000, tmk5904, dbgh9129
In-Reply-To: <20260420010118.17960-1-dbgh9129@gmail.com>
Dear Helge and Jason,
I am sending a gentle ping on this patch. Please let me know if you
have any feedback or if any changes are required.
Best regards,
Yuho Choi
^ permalink raw reply
* [PATCH 6.6.y] fbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_info
From: Sasha Levin @ 2026-05-05 6:00 UTC (permalink / raw)
To: stable; +Cc: Thomas Zimmermann, Helge Deller, linux-fbdev, dri-devel,
Sasha Levin
In-Reply-To: <2026050116-clean-cure-c52e@gregkh>
From: Thomas Zimmermann <tzimmermann@suse.de>
[ Upstream commit 9ded47ad003f09a94b6a710b5c47f4aa5ceb7429 ]
Hold state of deferred I/O in struct fb_deferred_io_state. Allocate an
instance as part of initializing deferred I/O and remove it only after
the final mapping has been closed. If the fb_info and the contained
deferred I/O meanwhile goes away, clear struct fb_deferred_io_state.info
to invalidate the mapping. Any access will then result in a SIGBUS
signal.
Fixes a long-standing problem, where a device hot-unplug happens while
user space still has an active mapping of the graphics memory. The hot-
unplug frees the instance of struct fb_info. Accessing the memory will
operate on undefined state.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 60b59beafba8 ("fbdev: mm: Deferred IO support")
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: stable@vger.kernel.org # v2.6.22+
Signed-off-by: Helge Deller <deller@gmx.de>
[ replaced `kzalloc_obj` with `kzalloc`, and dropped `mutex_destroy(&fbdefio->lock)` ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/video/fbdev/core/fb_defio.c | 179 ++++++++++++++++++++++------
include/linux/fb.h | 4 +-
2 files changed, 145 insertions(+), 38 deletions(-)
diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c
index b9607d5a370d4..f4812a76c3cc0 100644
--- a/drivers/video/fbdev/core/fb_defio.c
+++ b/drivers/video/fbdev/core/fb_defio.c
@@ -23,6 +23,75 @@
#include <linux/rmap.h>
#include <linux/pagemap.h>
+/*
+ * struct fb_deferred_io_state
+ */
+
+struct fb_deferred_io_state {
+ struct kref ref;
+
+ struct mutex lock; /* mutex that protects the pageref list */
+ /* fields protected by lock */
+ struct fb_info *info;
+};
+
+static struct fb_deferred_io_state *fb_deferred_io_state_alloc(void)
+{
+ struct fb_deferred_io_state *fbdefio_state;
+
+ fbdefio_state = kzalloc(sizeof(*fbdefio_state), GFP_KERNEL);
+ if (!fbdefio_state)
+ return NULL;
+
+ kref_init(&fbdefio_state->ref);
+ mutex_init(&fbdefio_state->lock);
+
+ return fbdefio_state;
+}
+
+static void fb_deferred_io_state_release(struct fb_deferred_io_state *fbdefio_state)
+{
+ mutex_destroy(&fbdefio_state->lock);
+
+ kfree(fbdefio_state);
+}
+
+static void fb_deferred_io_state_get(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_get(&fbdefio_state->ref);
+}
+
+static void __fb_deferred_io_state_release(struct kref *ref)
+{
+ struct fb_deferred_io_state *fbdefio_state =
+ container_of(ref, struct fb_deferred_io_state, ref);
+
+ fb_deferred_io_state_release(fbdefio_state);
+}
+
+static void fb_deferred_io_state_put(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_put(&fbdefio_state->ref, __fb_deferred_io_state_release);
+}
+
+/*
+ * struct vm_operations_struct
+ */
+
+static void fb_deferred_io_vm_open(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_get(fbdefio_state);
+}
+
+static void fb_deferred_io_vm_close(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_put(fbdefio_state);
+}
+
static struct page *fb_deferred_io_page(struct fb_info *info, unsigned long offs)
{
void *screen_base = (void __force *) info->screen_base;
@@ -93,17 +162,31 @@ static void fb_deferred_io_pageref_put(struct fb_deferred_io_pageref *pageref,
/* this is to find and return the vmalloc-ed fb pages */
static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
{
+ struct fb_info *info;
unsigned long offset;
struct page *page;
- struct fb_info *info = vmf->vma->vm_private_data;
+ vm_fault_t ret;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
+
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
offset = vmf->pgoff << PAGE_SHIFT;
- if (offset >= info->fix.smem_len)
- return VM_FAULT_SIGBUS;
+ if (offset >= info->fix.smem_len) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
page = fb_deferred_io_page(info, offset);
- if (!page)
- return VM_FAULT_SIGBUS;
+ if (!page) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
get_page(page);
@@ -115,8 +198,15 @@ static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
BUG_ON(!page->mapping);
page->index = vmf->pgoff; /* for page_mkclean() */
+ mutex_unlock(&fbdefio_state->lock);
+
vmf->page = page;
+
return 0;
+
+err_mutex_unlock:
+ mutex_unlock(&fbdefio_state->lock);
+ return ret;
}
int fb_deferred_io_fsync(struct file *file, loff_t start, loff_t end, int datasync)
@@ -143,15 +233,24 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_fsync);
* Adds a page to the dirty list. Call this from struct
* vm_operations_struct.page_mkwrite.
*/
-static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long offset,
- struct page *page)
+static vm_fault_t fb_deferred_io_track_page(struct fb_deferred_io_state *fbdefio_state,
+ unsigned long offset, struct page *page)
{
- struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_info *info;
+ struct fb_deferred_io *fbdefio;
struct fb_deferred_io_pageref *pageref;
vm_fault_t ret;
/* protect against the workqueue changing the page list */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
+
+ fbdefio = info->fbdefio;
pageref = fb_deferred_io_pageref_get(info, offset, page);
if (WARN_ON_ONCE(!pageref)) {
@@ -169,50 +268,38 @@ static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long
*/
lock_page(pageref->page);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
/* come back after delay to process the deferred IO */
schedule_delayed_work(&info->deferred_work, fbdefio->delay);
return VM_FAULT_LOCKED;
err_mutex_unlock:
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
return ret;
}
-/*
- * fb_deferred_io_page_mkwrite - Mark a page as written for deferred I/O
- * @fb_info: The fbdev info structure
- * @vmf: The VM fault
- *
- * This is a callback we get when userspace first tries to
- * write to the page. We schedule a workqueue. That workqueue
- * will eventually mkclean the touched pages and execute the
- * deferred framebuffer IO. Then if userspace touches a page
- * again, we repeat the same scheme.
- *
- * Returns:
- * VM_FAULT_LOCKED on success, or a VM_FAULT error otherwise.
- */
-static vm_fault_t fb_deferred_io_page_mkwrite(struct fb_info *info, struct vm_fault *vmf)
+static vm_fault_t fb_deferred_io_page_mkwrite(struct fb_deferred_io_state *fbdefio_state,
+ struct vm_fault *vmf)
{
unsigned long offset = vmf->pgoff << PAGE_SHIFT;
struct page *page = vmf->page;
file_update_time(vmf->vma->vm_file);
- return fb_deferred_io_track_page(info, offset, page);
+ return fb_deferred_io_track_page(fbdefio_state, offset, page);
}
-/* vm_ops->page_mkwrite handler */
static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
{
- struct fb_info *info = vmf->vma->vm_private_data;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
- return fb_deferred_io_page_mkwrite(info, vmf);
+ return fb_deferred_io_page_mkwrite(fbdefio_state, vmf);
}
static const struct vm_operations_struct fb_deferred_io_vm_ops = {
+ .open = fb_deferred_io_vm_open,
+ .close = fb_deferred_io_vm_close,
.fault = fb_deferred_io_fault,
.page_mkwrite = fb_deferred_io_mkwrite,
};
@@ -227,7 +314,10 @@ int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma)
vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
if (!(info->flags & FBINFO_VIRTFB))
vm_flags_set(vma, VM_IO);
- vma->vm_private_data = info;
+ vma->vm_private_data = info->fbdefio_state;
+
+ fb_deferred_io_state_get(info->fbdefio_state); /* released in vma->vm_ops->close() */
+
return 0;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_mmap);
@@ -238,9 +328,10 @@ static void fb_deferred_io_work(struct work_struct *work)
struct fb_info *info = container_of(work, struct fb_info, deferred_work.work);
struct fb_deferred_io_pageref *pageref, *next;
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
/* here we mkclean the pages, then do all deferred IO */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
list_for_each_entry(pageref, &fbdefio->pagereflist, list) {
struct page *cur = pageref->page;
lock_page(cur);
@@ -255,12 +346,13 @@ static void fb_deferred_io_work(struct work_struct *work)
list_for_each_entry_safe(pageref, next, &fbdefio->pagereflist, list)
fb_deferred_io_pageref_put(pageref, info);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
}
int fb_deferred_io_init(struct fb_info *info)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
struct fb_deferred_io_pageref *pagerefs;
unsigned long npagerefs, i;
int ret;
@@ -270,7 +362,11 @@ int fb_deferred_io_init(struct fb_info *info)
if (WARN_ON(!info->fix.smem_len))
return -EINVAL;
- mutex_init(&fbdefio->lock);
+ fbdefio_state = fb_deferred_io_state_alloc();
+ if (!fbdefio_state)
+ return -ENOMEM;
+ fbdefio_state->info = info;
+
INIT_DELAYED_WORK(&info->deferred_work, fb_deferred_io_work);
INIT_LIST_HEAD(&fbdefio->pagereflist);
if (fbdefio->delay == 0) /* set a default of 1 s */
@@ -289,10 +385,12 @@ int fb_deferred_io_init(struct fb_info *info)
info->npagerefs = npagerefs;
info->pagerefs = pagerefs;
+ info->fbdefio_state = fbdefio_state;
+
return 0;
err:
- mutex_destroy(&fbdefio->lock);
+ fb_deferred_io_state_release(fbdefio_state);
return ret;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_init);
@@ -333,11 +431,18 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_release);
void fb_deferred_io_cleanup(struct fb_info *info)
{
- struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
fb_deferred_io_lastclose(info);
+ info->fbdefio_state = NULL;
+
+ mutex_lock(&fbdefio_state->lock);
+ fbdefio_state->info = NULL;
+ mutex_unlock(&fbdefio_state->lock);
+
+ fb_deferred_io_state_put(fbdefio_state);
+
kvfree(info->pagerefs);
- mutex_destroy(&fbdefio->lock);
}
EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 322b4d20afa55..8a9d949cc7e2d 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -214,11 +214,12 @@ struct fb_deferred_io {
unsigned long delay;
bool sort_pagereflist; /* sort pagelist by offset */
int open_count; /* number of opened files; protected by fb_info lock */
- struct mutex lock; /* mutex that protects the pageref list */
struct list_head pagereflist; /* list of pagerefs for touched pages */
/* callback */
void (*deferred_io)(struct fb_info *info, struct list_head *pagelist);
};
+
+struct fb_deferred_io_state;
#endif
/*
@@ -476,6 +477,7 @@ struct fb_info {
unsigned long npagerefs;
struct fb_deferred_io_pageref *pagerefs;
struct fb_deferred_io *fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
#endif
const struct fb_ops *fbops;
--
2.53.0
^ permalink raw reply related
* [PATCH 6.1.y] fbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_info
From: Sasha Levin @ 2026-05-05 7:31 UTC (permalink / raw)
To: stable; +Cc: Thomas Zimmermann, Helge Deller, linux-fbdev, dri-devel,
Sasha Levin
In-Reply-To: <2026050117-caravan-atrocious-ee79@gregkh>
From: Thomas Zimmermann <tzimmermann@suse.de>
[ Upstream commit 9ded47ad003f09a94b6a710b5c47f4aa5ceb7429 ]
Hold state of deferred I/O in struct fb_deferred_io_state. Allocate an
instance as part of initializing deferred I/O and remove it only after
the final mapping has been closed. If the fb_info and the contained
deferred I/O meanwhile goes away, clear struct fb_deferred_io_state.info
to invalidate the mapping. Any access will then result in a SIGBUS
signal.
Fixes a long-standing problem, where a device hot-unplug happens while
user space still has an active mapping of the graphics memory. The hot-
unplug frees the instance of struct fb_info. Accessing the memory will
operate on undefined state.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 60b59beafba8 ("fbdev: mm: Deferred IO support")
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: stable@vger.kernel.org # v2.6.22+
Signed-off-by: Helge Deller <deller@gmx.de>
[ context + _obj() conversion ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/video/fbdev/core/fb_defio.c | 164 ++++++++++++++++++++++++----
include/linux/fb.h | 4 +-
2 files changed, 145 insertions(+), 23 deletions(-)
diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c
index 3b376345d4d47..7ac0bf4766b34 100644
--- a/drivers/video/fbdev/core/fb_defio.c
+++ b/drivers/video/fbdev/core/fb_defio.c
@@ -23,6 +23,75 @@
#include <linux/rmap.h>
#include <linux/pagemap.h>
+/*
+ * struct fb_deferred_io_state
+ */
+
+struct fb_deferred_io_state {
+ struct kref ref;
+
+ struct mutex lock; /* mutex that protects the pageref list */
+ /* fields protected by lock */
+ struct fb_info *info;
+};
+
+static struct fb_deferred_io_state *fb_deferred_io_state_alloc(void)
+{
+ struct fb_deferred_io_state *fbdefio_state;
+
+ fbdefio_state = kzalloc(sizeof(*fbdefio_state), GFP_KERNEL);
+ if (!fbdefio_state)
+ return NULL;
+
+ kref_init(&fbdefio_state->ref);
+ mutex_init(&fbdefio_state->lock);
+
+ return fbdefio_state;
+}
+
+static void fb_deferred_io_state_release(struct fb_deferred_io_state *fbdefio_state)
+{
+ mutex_destroy(&fbdefio_state->lock);
+
+ kfree(fbdefio_state);
+}
+
+static void fb_deferred_io_state_get(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_get(&fbdefio_state->ref);
+}
+
+static void __fb_deferred_io_state_release(struct kref *ref)
+{
+ struct fb_deferred_io_state *fbdefio_state =
+ container_of(ref, struct fb_deferred_io_state, ref);
+
+ fb_deferred_io_state_release(fbdefio_state);
+}
+
+static void fb_deferred_io_state_put(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_put(&fbdefio_state->ref, __fb_deferred_io_state_release);
+}
+
+/*
+ * struct vm_operations_struct
+ */
+
+static void fb_deferred_io_vm_open(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_get(fbdefio_state);
+}
+
+static void fb_deferred_io_vm_close(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_put(fbdefio_state);
+}
+
static struct page *fb_deferred_io_page(struct fb_info *info, unsigned long offs)
{
void *screen_base = (void __force *) info->screen_base;
@@ -93,17 +162,31 @@ static void fb_deferred_io_pageref_put(struct fb_deferred_io_pageref *pageref,
/* this is to find and return the vmalloc-ed fb pages */
static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
{
+ struct fb_info *info;
unsigned long offset;
struct page *page;
- struct fb_info *info = vmf->vma->vm_private_data;
+ vm_fault_t ret;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
+
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
offset = vmf->pgoff << PAGE_SHIFT;
- if (offset >= info->fix.smem_len)
- return VM_FAULT_SIGBUS;
+ if (offset >= info->fix.smem_len) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
page = fb_deferred_io_page(info, offset);
- if (!page)
- return VM_FAULT_SIGBUS;
+ if (!page) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
get_page(page);
@@ -115,8 +198,15 @@ static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
BUG_ON(!page->mapping);
page->index = vmf->pgoff; /* for page_mkclean() */
+ mutex_unlock(&fbdefio_state->lock);
+
vmf->page = page;
+
return 0;
+
+err_mutex_unlock:
+ mutex_unlock(&fbdefio_state->lock);
+ return ret;
}
int fb_deferred_io_fsync(struct file *file, loff_t start, loff_t end, int datasync)
@@ -143,15 +233,24 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_fsync);
* Adds a page to the dirty list. Call this from struct
* vm_operations_struct.page_mkwrite.
*/
-static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long offset,
- struct page *page)
+static vm_fault_t fb_deferred_io_track_page(struct fb_deferred_io_state *fbdefio_state,
+ unsigned long offset, struct page *page)
{
- struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_info *info;
+ struct fb_deferred_io *fbdefio;
struct fb_deferred_io_pageref *pageref;
vm_fault_t ret;
/* protect against the workqueue changing the page list */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
+
+ fbdefio = info->fbdefio;
/* first write in this cycle, notify the driver */
if (fbdefio->first_io && list_empty(&fbdefio->pagereflist))
@@ -173,14 +272,14 @@ static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long
*/
lock_page(pageref->page);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
/* come back after delay to process the deferred IO */
schedule_delayed_work(&info->deferred_work, fbdefio->delay);
return VM_FAULT_LOCKED;
err_mutex_unlock:
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
return ret;
}
@@ -198,25 +297,28 @@ static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long
* Returns:
* VM_FAULT_LOCKED on success, or a VM_FAULT error otherwise.
*/
-static vm_fault_t fb_deferred_io_page_mkwrite(struct fb_info *info, struct vm_fault *vmf)
+static vm_fault_t fb_deferred_io_page_mkwrite(struct fb_deferred_io_state *fbdefio_state,
+ struct vm_fault *vmf)
{
unsigned long offset = vmf->pgoff << PAGE_SHIFT;
struct page *page = vmf->page;
file_update_time(vmf->vma->vm_file);
- return fb_deferred_io_track_page(info, offset, page);
+ return fb_deferred_io_track_page(fbdefio_state, offset, page);
}
/* vm_ops->page_mkwrite handler */
static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
{
- struct fb_info *info = vmf->vma->vm_private_data;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
- return fb_deferred_io_page_mkwrite(info, vmf);
+ return fb_deferred_io_page_mkwrite(fbdefio_state, vmf);
}
static const struct vm_operations_struct fb_deferred_io_vm_ops = {
+ .open = fb_deferred_io_vm_open,
+ .close = fb_deferred_io_vm_close,
.fault = fb_deferred_io_fault,
.page_mkwrite = fb_deferred_io_mkwrite,
};
@@ -231,7 +333,10 @@ int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma)
vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
if (!(info->flags & FBINFO_VIRTFB))
vma->vm_flags |= VM_IO;
- vma->vm_private_data = info;
+ vma->vm_private_data = info->fbdefio_state;
+
+ fb_deferred_io_state_get(info->fbdefio_state); /* released in vma->vm_ops->close() */
+
return 0;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_mmap);
@@ -242,9 +347,10 @@ static void fb_deferred_io_work(struct work_struct *work)
struct fb_info *info = container_of(work, struct fb_info, deferred_work.work);
struct fb_deferred_io_pageref *pageref, *next;
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
/* here we mkclean the pages, then do all deferred IO */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
list_for_each_entry(pageref, &fbdefio->pagereflist, list) {
struct page *cur = pageref->page;
lock_page(cur);
@@ -259,12 +365,13 @@ static void fb_deferred_io_work(struct work_struct *work)
list_for_each_entry_safe(pageref, next, &fbdefio->pagereflist, list)
fb_deferred_io_pageref_put(pageref, info);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
}
int fb_deferred_io_init(struct fb_info *info)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
struct fb_deferred_io_pageref *pagerefs;
unsigned long npagerefs, i;
int ret;
@@ -274,7 +381,11 @@ int fb_deferred_io_init(struct fb_info *info)
if (WARN_ON(!info->fix.smem_len))
return -EINVAL;
- mutex_init(&fbdefio->lock);
+ fbdefio_state = fb_deferred_io_state_alloc();
+ if (!fbdefio_state)
+ return -ENOMEM;
+ fbdefio_state->info = info;
+
INIT_DELAYED_WORK(&info->deferred_work, fb_deferred_io_work);
INIT_LIST_HEAD(&fbdefio->pagereflist);
if (fbdefio->delay == 0) /* set a default of 1 s */
@@ -293,10 +404,12 @@ int fb_deferred_io_init(struct fb_info *info)
info->npagerefs = npagerefs;
info->pagerefs = pagerefs;
+ info->fbdefio_state = fbdefio_state;
+
return 0;
err:
- mutex_destroy(&fbdefio->lock);
+ fb_deferred_io_state_release(fbdefio_state);
return ret;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_init);
@@ -337,11 +450,18 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_release);
void fb_deferred_io_cleanup(struct fb_info *info)
{
- struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
fb_deferred_io_lastclose(info);
+ info->fbdefio_state = NULL;
+
+ mutex_lock(&fbdefio_state->lock);
+ fbdefio_state->info = NULL;
+ mutex_unlock(&fbdefio_state->lock);
+
+ fb_deferred_io_state_put(fbdefio_state);
+
kvfree(info->pagerefs);
- mutex_destroy(&fbdefio->lock);
}
EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index c7f0f14e1f74b..5f94c58c4672e 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -213,12 +213,13 @@ struct fb_deferred_io {
unsigned long delay;
bool sort_pagereflist; /* sort pagelist by offset */
int open_count; /* number of opened files; protected by fb_info lock */
- struct mutex lock; /* mutex that protects the pageref list */
struct list_head pagereflist; /* list of pagerefs for touched pages */
/* callback */
void (*first_io)(struct fb_info *info);
void (*deferred_io)(struct fb_info *info, struct list_head *pagelist);
};
+
+struct fb_deferred_io_state;
#endif
/*
@@ -479,6 +480,7 @@ struct fb_info {
unsigned long npagerefs;
struct fb_deferred_io_pageref *pagerefs;
struct fb_deferred_io *fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
#endif
const struct fb_ops *fbops;
--
2.53.0
^ permalink raw reply related
* Re: [PATCH v2] staging: sm750fb: add const qualifier to string pointer arrays
From: kernel test robot @ 2026-05-05 8:11 UTC (permalink / raw)
To: Francisco Maestre, sudipm.mukherjee, teddy.wang, gregkh
Cc: llvm, oe-kbuild-all, linux-fbdev, linux-staging, linux-kernel,
Francisco Maestre
In-Reply-To: <20260503005744.68974-1-francisco@maestretorreblanca.com>
Hi Francisco,
kernel test robot noticed the following build errors:
[auto build test ERROR on staging/staging-testing]
url: https://github.com/intel-lab-lkp/linux/commits/Francisco-Maestre/staging-sm750fb-add-const-qualifier-to-string-pointer-arrays/20260503-215917
base: staging/staging-testing
patch link: https://lore.kernel.org/r/20260503005744.68974-1-francisco%40maestretorreblanca.com
patch subject: [PATCH v2] staging: sm750fb: add const qualifier to string pointer arrays
config: loongarch-allmodconfig (https://download.01.org/0day-ci/archive/20260505/202605051602.dWbzp24c-lkp@intel.com/config)
compiler: clang version 19.1.7 (https://github.com/llvm/llvm-project cd708029e0b2869e80abe31ddb175f7c35361f90)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260505/202605051602.dWbzp24c-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605051602.dWbzp24c-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/staging/sm750fb/sm750.c:785:19: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
785 | g_fbmode[index] = g_def_fbmode;
| ~~~~~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:36:27: note: variable 'g_fbmode' declared const here
36 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/sm750fb/sm750.c:787:20: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
787 | g_fbmode[index] = g_fbmode[0];
| ~~~~~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:36:27: note: variable 'g_fbmode' declared const here
36 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/sm750fb/sm750.c:896:17: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
896 | g_fbmode[0] = opt;
| ~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:36:27: note: variable 'g_fbmode' declared const here
36 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/sm750fb/sm750.c:900:17: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
900 | g_fbmode[1] = opt;
| ~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:36:27: note: variable 'g_fbmode' declared const here
36 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
4 errors generated.
vim +785 drivers/staging/sm750fb/sm750.c
81dee67e215b23 Sudip Mukherjee 2015-03-03 719
81dee67e215b23 Sudip Mukherjee 2015-03-03 720 static int lynxfb_set_fbinfo(struct fb_info *info, int index)
81dee67e215b23 Sudip Mukherjee 2015-03-03 721 {
81dee67e215b23 Sudip Mukherjee 2015-03-03 722 int i;
81dee67e215b23 Sudip Mukherjee 2015-03-03 723 struct lynxfb_par *par;
e359b6a863e19f Mike Rapoport 2015-10-26 724 struct sm750_dev *sm750_dev;
81dee67e215b23 Sudip Mukherjee 2015-03-03 725 struct lynxfb_crtc *crtc;
81dee67e215b23 Sudip Mukherjee 2015-03-03 726 struct lynxfb_output *output;
81dee67e215b23 Sudip Mukherjee 2015-03-03 727 struct fb_var_screeninfo *var;
81dee67e215b23 Sudip Mukherjee 2015-03-03 728 struct fb_fix_screeninfo *fix;
81dee67e215b23 Sudip Mukherjee 2015-03-03 729
81dee67e215b23 Sudip Mukherjee 2015-03-03 730 const struct fb_videomode *pdb[] = {
81dee67e215b23 Sudip Mukherjee 2015-03-03 731 lynx750_ext, NULL, vesa_modes,
81dee67e215b23 Sudip Mukherjee 2015-03-03 732 };
81dee67e215b23 Sudip Mukherjee 2015-03-03 733 int cdb[] = {ARRAY_SIZE(lynx750_ext), 0, VESA_MODEDB_SIZE};
d0856045f0e9fc Hungyu Lin 2026-04-01 734 static const char * const fix_id[2] = {
81dee67e215b23 Sudip Mukherjee 2015-03-03 735 "sm750_fb1", "sm750_fb2",
81dee67e215b23 Sudip Mukherjee 2015-03-03 736 };
81dee67e215b23 Sudip Mukherjee 2015-03-03 737
81dee67e215b23 Sudip Mukherjee 2015-03-03 738 int ret, line_length;
81dee67e215b23 Sudip Mukherjee 2015-03-03 739
81dee67e215b23 Sudip Mukherjee 2015-03-03 740 ret = 0;
81dee67e215b23 Sudip Mukherjee 2015-03-03 741 par = (struct lynxfb_par *)info->par;
e359b6a863e19f Mike Rapoport 2015-10-26 742 sm750_dev = par->dev;
81dee67e215b23 Sudip Mukherjee 2015-03-03 743 crtc = &par->crtc;
81dee67e215b23 Sudip Mukherjee 2015-03-03 744 output = &par->output;
81dee67e215b23 Sudip Mukherjee 2015-03-03 745 var = &info->var;
81dee67e215b23 Sudip Mukherjee 2015-03-03 746 fix = &info->fix;
81dee67e215b23 Sudip Mukherjee 2015-03-03 747
81dee67e215b23 Sudip Mukherjee 2015-03-03 748 /* set index */
81dee67e215b23 Sudip Mukherjee 2015-03-03 749 par->index = index;
81dee67e215b23 Sudip Mukherjee 2015-03-03 750 output->channel = &crtc->channel;
81dee67e215b23 Sudip Mukherjee 2015-03-03 751 sm750fb_set_drv(par);
81dee67e215b23 Sudip Mukherjee 2015-03-03 752
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 753 /*
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 754 * set current cursor variable and proc pointer,
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 755 * must be set after crtc member initialized
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 756 */
fdc234d85210d9 Benjamin Philip 2021-07-28 757 crtc->cursor.offset = crtc->o_screen + crtc->vidmem_size - 1024;
e359b6a863e19f Mike Rapoport 2015-10-26 758 crtc->cursor.mmio = sm750_dev->pvReg +
e359b6a863e19f Mike Rapoport 2015-10-26 759 0x800f0 + (int)crtc->channel * 0x140;
81dee67e215b23 Sudip Mukherjee 2015-03-03 760
cd33da26036ea5 Christopher Carbone 2022-08-23 761 crtc->cursor.max_h = 64;
cd33da26036ea5 Christopher Carbone 2022-08-23 762 crtc->cursor.max_w = 64;
39f9137268ee3d Benjamin Philip 2021-07-26 763 crtc->cursor.size = crtc->cursor.max_h * crtc->cursor.max_w * 2 / 8;
e359b6a863e19f Mike Rapoport 2015-10-26 764 crtc->cursor.vstart = sm750_dev->pvMem + crtc->cursor.offset;
81dee67e215b23 Sudip Mukherjee 2015-03-03 765
3de08a2d14ff8c Lorenzo Stoakes 2015-03-20 766 memset_io(crtc->cursor.vstart, 0, crtc->cursor.size);
f7c8a046577e09 Thomas Zimmermann 2023-11-27 767 if (!g_hwcursor)
52d0744d751d8f Arnd Bergmann 2016-11-09 768 sm750_hw_cursor_disable(&crtc->cursor);
81dee67e215b23 Sudip Mukherjee 2015-03-03 769
81dee67e215b23 Sudip Mukherjee 2015-03-03 770 /* set info->fbops, must be set before fb_find_mode */
e359b6a863e19f Mike Rapoport 2015-10-26 771 if (!sm750_dev->accel_off) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 772 /* use 2d acceleration */
f7c8a046577e09 Thomas Zimmermann 2023-11-27 773 if (!g_hwcursor)
f7c8a046577e09 Thomas Zimmermann 2023-11-27 774 info->fbops = &lynxfb_ops_accel;
f7c8a046577e09 Thomas Zimmermann 2023-11-27 775 else
f7c8a046577e09 Thomas Zimmermann 2023-11-27 776 info->fbops = &lynxfb_ops_accel_with_cursor;
f7c8a046577e09 Thomas Zimmermann 2023-11-27 777 } else {
f7c8a046577e09 Thomas Zimmermann 2023-11-27 778 if (!g_hwcursor)
81dee67e215b23 Sudip Mukherjee 2015-03-03 779 info->fbops = &lynxfb_ops;
f7c8a046577e09 Thomas Zimmermann 2023-11-27 780 else
f7c8a046577e09 Thomas Zimmermann 2023-11-27 781 info->fbops = &lynxfb_ops_with_cursor;
f7c8a046577e09 Thomas Zimmermann 2023-11-27 782 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 783
81dee67e215b23 Sudip Mukherjee 2015-03-03 784 if (!g_fbmode[index]) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 @785 g_fbmode[index] = g_def_fbmode;
81dee67e215b23 Sudip Mukherjee 2015-03-03 786 if (index)
81dee67e215b23 Sudip Mukherjee 2015-03-03 787 g_fbmode[index] = g_fbmode[0];
81dee67e215b23 Sudip Mukherjee 2015-03-03 788 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 789
81dee67e215b23 Sudip Mukherjee 2015-03-03 790 for (i = 0; i < 3; i++) {
81dee67e215b23 Sudip Mukherjee 2015-03-03 791 ret = fb_find_mode(var, info, g_fbmode[index],
81dee67e215b23 Sudip Mukherjee 2015-03-03 792 pdb[i], cdb[i], NULL, 8);
81dee67e215b23 Sudip Mukherjee 2015-03-03 793
db7fb3588ab492 Artem Lytkin 2026-02-23 794 if (ret == 1 || ret == 2)
81dee67e215b23 Sudip Mukherjee 2015-03-03 795 break;
81dee67e215b23 Sudip Mukherjee 2015-03-03 796 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 797
81dee67e215b23 Sudip Mukherjee 2015-03-03 798 /* set par */
81dee67e215b23 Sudip Mukherjee 2015-03-03 799 par->info = info;
81dee67e215b23 Sudip Mukherjee 2015-03-03 800
81dee67e215b23 Sudip Mukherjee 2015-03-03 801 /* set info */
e3a3f9f5123683 Mike Rapoport 2015-10-26 802 line_length = ALIGN((var->xres_virtual * var->bits_per_pixel / 8),
e3a3f9f5123683 Mike Rapoport 2015-10-26 803 crtc->line_pad);
81dee67e215b23 Sudip Mukherjee 2015-03-03 804
81dee67e215b23 Sudip Mukherjee 2015-03-03 805 info->pseudo_palette = &par->pseudo_palette[0];
cc59bde1c920ab Benjamin Philip 2021-07-28 806 info->screen_base = crtc->v_screen;
81dee67e215b23 Sudip Mukherjee 2015-03-03 807 info->screen_size = line_length * var->yres_virtual;
81dee67e215b23 Sudip Mukherjee 2015-03-03 808
81dee67e215b23 Sudip Mukherjee 2015-03-03 809 /* set info->fix */
81dee67e215b23 Sudip Mukherjee 2015-03-03 810 fix->type = FB_TYPE_PACKED_PIXELS;
81dee67e215b23 Sudip Mukherjee 2015-03-03 811 fix->type_aux = 0;
81dee67e215b23 Sudip Mukherjee 2015-03-03 812 fix->xpanstep = crtc->xpanstep;
81dee67e215b23 Sudip Mukherjee 2015-03-03 813 fix->ypanstep = crtc->ypanstep;
81dee67e215b23 Sudip Mukherjee 2015-03-03 814 fix->ywrapstep = crtc->ywrapstep;
81dee67e215b23 Sudip Mukherjee 2015-03-03 815 fix->accel = FB_ACCEL_SMI;
81dee67e215b23 Sudip Mukherjee 2015-03-03 816
8c475735085a7d Tim Wassink 2025-12-21 817 strscpy(fix->id, fix_id[index], sizeof(fix->id));
81dee67e215b23 Sudip Mukherjee 2015-03-03 818
fdc234d85210d9 Benjamin Philip 2021-07-28 819 fix->smem_start = crtc->o_screen + sm750_dev->vidmem_start;
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 820 /*
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 821 * according to mmap experiment from user space application,
81dee67e215b23 Sudip Mukherjee 2015-03-03 822 * fix->mmio_len should not larger than virtual size
81dee67e215b23 Sudip Mukherjee 2015-03-03 823 * (xres_virtual x yres_virtual x ByPP)
81dee67e215b23 Sudip Mukherjee 2015-03-03 824 * Below line maybe buggy when user mmap fb dev node and write
81dee67e215b23 Sudip Mukherjee 2015-03-03 825 * data into the bound over virtual size
d11ac7cbcc266c Sudip Mukherjee 2015-08-07 826 */
81dee67e215b23 Sudip Mukherjee 2015-03-03 827 fix->smem_len = crtc->vidmem_size;
81dee67e215b23 Sudip Mukherjee 2015-03-03 828 info->screen_size = fix->smem_len;
81dee67e215b23 Sudip Mukherjee 2015-03-03 829 fix->line_length = line_length;
e359b6a863e19f Mike Rapoport 2015-10-26 830 fix->mmio_start = sm750_dev->vidreg_start;
e359b6a863e19f Mike Rapoport 2015-10-26 831 fix->mmio_len = sm750_dev->vidreg_size;
b610e1193a917f Matej Dujava 2020-04-30 832
b610e1193a917f Matej Dujava 2020-04-30 833 lynxfb_set_visual_mode(info);
81dee67e215b23 Sudip Mukherjee 2015-03-03 834
81dee67e215b23 Sudip Mukherjee 2015-03-03 835 /* set var */
81dee67e215b23 Sudip Mukherjee 2015-03-03 836 var->activate = FB_ACTIVATE_NOW;
81dee67e215b23 Sudip Mukherjee 2015-03-03 837 var->accel_flags = 0;
81dee67e215b23 Sudip Mukherjee 2015-03-03 838 var->vmode = FB_VMODE_NONINTERLACED;
81dee67e215b23 Sudip Mukherjee 2015-03-03 839
61c507cf652da1 Michel von Czettritz 2015-03-26 840 ret = fb_alloc_cmap(&info->cmap, 256, 0);
61c507cf652da1 Michel von Czettritz 2015-03-26 841 if (ret < 0) {
fbab250eb51d6d Artem Lytkin 2026-02-07 842 dev_err(info->device, "Could not allocate memory for cmap.\n");
81dee67e215b23 Sudip Mukherjee 2015-03-03 843 goto exit;
81dee67e215b23 Sudip Mukherjee 2015-03-03 844 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 845
81dee67e215b23 Sudip Mukherjee 2015-03-03 846 exit:
81dee67e215b23 Sudip Mukherjee 2015-03-03 847 lynxfb_ops_check_var(var, info);
81dee67e215b23 Sudip Mukherjee 2015-03-03 848 return ret;
81dee67e215b23 Sudip Mukherjee 2015-03-03 849 }
81dee67e215b23 Sudip Mukherjee 2015-03-03 850
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply
* [PATCH 5.15.y] fbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_info
From: Sasha Levin @ 2026-05-05 9:49 UTC (permalink / raw)
To: stable; +Cc: Thomas Zimmermann, Helge Deller, linux-fbdev, dri-devel,
Sasha Levin
In-Reply-To: <2026050117-upper-unhelpful-d8a9@gregkh>
From: Thomas Zimmermann <tzimmermann@suse.de>
[ Upstream commit 9ded47ad003f09a94b6a710b5c47f4aa5ceb7429 ]
Hold state of deferred I/O in struct fb_deferred_io_state. Allocate an
instance as part of initializing deferred I/O and remove it only after
the final mapping has been closed. If the fb_info and the contained
deferred I/O meanwhile goes away, clear struct fb_deferred_io_state.info
to invalidate the mapping. Any access will then result in a SIGBUS
signal.
Fixes a long-standing problem, where a device hot-unplug happens while
user space still has an active mapping of the graphics memory. The hot-
unplug frees the instance of struct fb_info. Accessing the memory will
operate on undefined state.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 60b59beafba8 ("fbdev: mm: Deferred IO support")
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: stable@vger.kernel.org # v2.6.22+
Signed-off-by: Helge Deller <deller@gmx.de>
[ replaced `kzalloc_obj()` with `kzalloc(sizeof(*fbdefio_state), GFP_KERNEL)` ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/video/fbdev/core/fb_defio.c | 152 ++++++++++++++++++++++++----
include/linux/fb.h | 4 +-
2 files changed, 138 insertions(+), 18 deletions(-)
diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c
index c2a0a936d5fb6..e348f4c15d81a 100644
--- a/drivers/video/fbdev/core/fb_defio.c
+++ b/drivers/video/fbdev/core/fb_defio.c
@@ -23,6 +23,75 @@
#include <linux/rmap.h>
#include <linux/pagemap.h>
+/*
+ * struct fb_deferred_io_state
+ */
+
+struct fb_deferred_io_state {
+ struct kref ref;
+
+ struct mutex lock; /* mutex that protects the pageref list */
+ /* fields protected by lock */
+ struct fb_info *info;
+};
+
+static struct fb_deferred_io_state *fb_deferred_io_state_alloc(void)
+{
+ struct fb_deferred_io_state *fbdefio_state;
+
+ fbdefio_state = kzalloc(sizeof(*fbdefio_state), GFP_KERNEL);
+ if (!fbdefio_state)
+ return NULL;
+
+ kref_init(&fbdefio_state->ref);
+ mutex_init(&fbdefio_state->lock);
+
+ return fbdefio_state;
+}
+
+static void fb_deferred_io_state_release(struct fb_deferred_io_state *fbdefio_state)
+{
+ mutex_destroy(&fbdefio_state->lock);
+
+ kfree(fbdefio_state);
+}
+
+static void fb_deferred_io_state_get(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_get(&fbdefio_state->ref);
+}
+
+static void __fb_deferred_io_state_release(struct kref *ref)
+{
+ struct fb_deferred_io_state *fbdefio_state =
+ container_of(ref, struct fb_deferred_io_state, ref);
+
+ fb_deferred_io_state_release(fbdefio_state);
+}
+
+static void fb_deferred_io_state_put(struct fb_deferred_io_state *fbdefio_state)
+{
+ kref_put(&fbdefio_state->ref, __fb_deferred_io_state_release);
+}
+
+/*
+ * struct vm_operations_struct
+ */
+
+static void fb_deferred_io_vm_open(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_get(fbdefio_state);
+}
+
+static void fb_deferred_io_vm_close(struct vm_area_struct *vma)
+{
+ struct fb_deferred_io_state *fbdefio_state = vma->vm_private_data;
+
+ fb_deferred_io_state_put(fbdefio_state);
+}
+
static struct page *fb_deferred_io_page(struct fb_info *info, unsigned long offs)
{
void *screen_base = (void __force *) info->screen_base;
@@ -93,17 +162,31 @@ static void fb_deferred_io_pageref_put(struct fb_deferred_io_pageref *pageref,
/* this is to find and return the vmalloc-ed fb pages */
static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
{
+ struct fb_info *info;
unsigned long offset;
struct page *page;
- struct fb_info *info = vmf->vma->vm_private_data;
+ vm_fault_t ret;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
+
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
offset = vmf->pgoff << PAGE_SHIFT;
- if (offset >= info->fix.smem_len)
- return VM_FAULT_SIGBUS;
+ if (offset >= info->fix.smem_len) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
page = fb_deferred_io_page(info, offset);
- if (!page)
- return VM_FAULT_SIGBUS;
+ if (!page) {
+ ret = VM_FAULT_SIGBUS;
+ goto err_mutex_unlock;
+ }
get_page(page);
@@ -115,8 +198,14 @@ static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf)
BUG_ON(!page->mapping);
page->index = vmf->pgoff; /* for page_mkclean() */
+ mutex_unlock(&fbdefio_state->lock);
+
vmf->page = page;
return 0;
+
+err_mutex_unlock:
+ mutex_unlock(&fbdefio_state->lock);
+ return ret;
}
int fb_deferred_io_fsync(struct file *file, loff_t start, loff_t end, int datasync)
@@ -143,8 +232,9 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_fsync);
static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
{
struct page *page = vmf->page;
- struct fb_info *info = vmf->vma->vm_private_data;
- struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = vmf->vma->vm_private_data;
+ struct fb_info *info;
+ struct fb_deferred_io *fbdefio;
struct fb_deferred_io_pageref *pageref;
unsigned long offset;
vm_fault_t ret;
@@ -160,7 +250,15 @@ static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
file_update_time(vmf->vma->vm_file);
/* protect against the workqueue changing the page list */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
+
+ info = fbdefio_state->info;
+ if (!info) {
+ ret = VM_FAULT_SIGBUS; /* our device is gone */
+ goto err_mutex_unlock;
+ }
+
+ fbdefio = info->fbdefio;
/* first write in this cycle, notify the driver */
if (fbdefio->first_io && list_empty(&fbdefio->pagereflist))
@@ -182,18 +280,20 @@ static vm_fault_t fb_deferred_io_mkwrite(struct vm_fault *vmf)
*/
lock_page(pageref->page);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
/* come back after delay to process the deferred IO */
schedule_delayed_work(&info->deferred_work, fbdefio->delay);
return VM_FAULT_LOCKED;
err_mutex_unlock:
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
return ret;
}
static const struct vm_operations_struct fb_deferred_io_vm_ops = {
+ .open = fb_deferred_io_vm_open,
+ .close = fb_deferred_io_vm_close,
.fault = fb_deferred_io_fault,
.page_mkwrite = fb_deferred_io_mkwrite,
};
@@ -215,7 +315,10 @@ int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma)
vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
if (!(info->flags & FBINFO_VIRTFB))
vma->vm_flags |= VM_IO;
- vma->vm_private_data = info;
+ vma->vm_private_data = info->fbdefio_state;
+
+ fb_deferred_io_state_get(info->fbdefio_state); /* released in vma->vm_ops->close() */
+
return 0;
}
@@ -225,9 +328,10 @@ static void fb_deferred_io_work(struct work_struct *work)
struct fb_info *info = container_of(work, struct fb_info, deferred_work.work);
struct fb_deferred_io_pageref *pageref, *next;
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
/* here we mkclean the pages, then do all deferred IO */
- mutex_lock(&fbdefio->lock);
+ mutex_lock(&fbdefio_state->lock);
list_for_each_entry(pageref, &fbdefio->pagereflist, list) {
struct page *cur = pageref->page;
lock_page(cur);
@@ -242,12 +346,13 @@ static void fb_deferred_io_work(struct work_struct *work)
list_for_each_entry_safe(pageref, next, &fbdefio->pagereflist, list)
fb_deferred_io_pageref_put(pageref, info);
- mutex_unlock(&fbdefio->lock);
+ mutex_unlock(&fbdefio_state->lock);
}
int fb_deferred_io_init(struct fb_info *info)
{
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
struct fb_deferred_io_pageref *pagerefs;
unsigned long npagerefs, i;
int ret;
@@ -257,7 +362,11 @@ int fb_deferred_io_init(struct fb_info *info)
if (WARN_ON(!info->fix.smem_len))
return -EINVAL;
- mutex_init(&fbdefio->lock);
+ fbdefio_state = fb_deferred_io_state_alloc();
+ if (!fbdefio_state)
+ return -ENOMEM;
+ fbdefio_state->info = info;
+
INIT_DELAYED_WORK(&info->deferred_work, fb_deferred_io_work);
INIT_LIST_HEAD(&fbdefio->pagereflist);
if (fbdefio->delay == 0) /* set a default of 1 s */
@@ -276,10 +385,12 @@ int fb_deferred_io_init(struct fb_info *info)
info->npagerefs = npagerefs;
info->pagerefs = pagerefs;
+ info->fbdefio_state = fbdefio_state;
+
return 0;
err:
- mutex_destroy(&fbdefio->lock);
+ fb_deferred_io_state_release(fbdefio_state);
return ret;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_init);
@@ -320,11 +431,18 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_release);
void fb_deferred_io_cleanup(struct fb_info *info)
{
- struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct fb_deferred_io_state *fbdefio_state = info->fbdefio_state;
fb_deferred_io_lastclose(info);
+ info->fbdefio_state = NULL;
+
+ mutex_lock(&fbdefio_state->lock);
+ fbdefio_state->info = NULL;
+ mutex_unlock(&fbdefio_state->lock);
+
+ fb_deferred_io_state_put(fbdefio_state);
+
kvfree(info->pagerefs);
- mutex_destroy(&fbdefio->lock);
}
EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index b79a833524efc..9b3c198b06826 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -213,12 +213,13 @@ struct fb_deferred_io {
unsigned long delay;
bool sort_pagereflist; /* sort pagelist by offset */
int open_count; /* number of opened files; protected by fb_info lock */
- struct mutex lock; /* mutex that protects the pageref list */
struct list_head pagereflist; /* list of pagerefs for touched pages */
/* callback */
void (*first_io)(struct fb_info *info);
void (*deferred_io)(struct fb_info *info, struct list_head *pagelist);
};
+
+struct fb_deferred_io_state;
#endif
/*
@@ -480,6 +481,7 @@ struct fb_info {
unsigned long npagerefs;
struct fb_deferred_io_pageref *pagerefs;
struct fb_deferred_io *fbdefio;
+ struct fb_deferred_io_state *fbdefio_state;
#endif
const struct fb_ops *fbops;
--
2.53.0
^ permalink raw reply related
* Plan to fix nvidia_wmi_ec backlight issues, help wanted
From: Hans de Goede @ 2026-05-05 9:50 UTC (permalink / raw)
To: Lee Jones, Daniel Thompson, Jingoo Han, Helge Deller,
Daniel Dadap, Rafael J. Wysocki
Cc: dri-devel@lists.freedesktop.org, linux-fbdev, linux-acpi
Hi All,
A while ago Nvidia introduced a new Nvidia specific firmware method
for controlling the backlight on laptops with runtime switchable
Nvidia hybrid graphics.
This is supported through the nvidia-wmi-ec-backlight driver, but has
never worked 100%.
The new WMI firmware interface has a method to ask the firmware if
the backlight is controlled though the EC and this the new WMI interface
should be used; or if it is directly controlled by the GPU and the GPU
driver's native backlight support should be used.
There are several bugs in the implementation of this on various laptops:
1. The method to get the backlight control source sometimes does not
report the correct value.
2. On some laptop models which method (native-gpu vs nvidia-wmi) works
changes at runtime, e.g. when plugging in a charger.
Known affected laptop models/bug reports about this:
- Acer Predator PH315-55: needs acpi_backlight=native
- Dell G15 5515 with RTX 3050: *needs* acpi_backlight=native
- Dell G15 5515 with RTX 3060: *breaks* with acpi_backlight=native
- Lenovo Legion Slim 7 2021
- https://bugzilla.kernel.org/show_bug.cgi?id=217026
- https://gitlab.gnome.org/GNOME/gnome-settings-daemon/-/work_items/784
- https://gitlab.freedesktop.org/drm/amd/-/issues/4512
- https://bugzilla.suse.com/show_bug.cgi?id=1217750
It turns out that under Windows both a WMI backlight driver and a GPU
native backlight driver get installed and Windows simply always calls
both when the backlight changes working around these kind of firmware
bugs.
When this first came up, about 2 years ago, I came up with the below
plan to fix this. Nvidia was supposed to work in implementing this,
but so far an implementation of this plan has not happened.
Note I do not have time to work on this myself. I'm posting this here
in the hope that either Nvidia will pick this up after all; or that
someone else can make this happen.
I'm more then happy to help answering any questions which may come up
while implementing this; and to review the resulting patches.
The plan
========
1. Modify the core backlight code to allow registering a backlight-device
for in kernel use only, disabling the registering of a class device under
/sys/class/backlight .
2. Add a new backlight-aggregate.c backlight driver, which exports a
devm_backlight_aggregate_register_or_add() function. Drivers can call
this passing in an existing backlight-device (with its sysfs interface
disabled). This either creates a singleton /sys/class/backlight/aggregate
device, or adds the passed in backlight to the existing singleton instance
if it already exists.
This new driver always exposes a range of 0-255 to userspace. This acts
as a proxie for any backlight-devices registered to be part of
the aggregate, forwarding any brightness set calls to all backlights,
scaled to their actual range. For reads this will report the last set
brightness value (starting with the value of the first registered
backlight-device).
3. Add a new nvidia_wmi_ec_and_native type to drivers/acpi/video_detect.c
for both DMI quirks and commandline handling.
4. Modify acpi_video_backlight_use_native() to also return true if
the __acpi_video_get_backlight_type() call there returns the new
acpi_backlight_nvidia_wmi_ec_and_native.
5. Add a new devm_backlight_device_register_native() helper which
calls __acpi_video_get_backlight_type(true, NULL) and if that returns
the new nvidia_wmi_ec_and_native type then registers the passed in
backlight with the flag to not register a sysfs class interface and
then on success calls the new devm_backlight_aggregate_register_or_add()
with the just registered backlight device; and if the returned type
instead is acpi_backlight_native register the passed in backlight
normally through devm_backlight_device_register()
5. Modify the i915 and amdgpu drivers to use the new
devm_backlight_device_register_native() helper. Since this new helper
checks the backlight-type itself, drop acpi_video_backlight_use_native()
checks *if* the registration is the only thing guarded by that check.
6. drivers/platform/x86/nvidia-wmi-ec-backlight.c to not return
early from probe when acpi_video_get_backlight_type() returns
the new nvidia_wmi_ec_and_native type and for that type make it
registers its backlight with the flag to not register a sysfs class
interface and then on success calls the new
devm_backlight_aggregate_register_or_add().
Regards,
Hans
^ permalink raw reply
* Plan to fix nvidia_wmi_ec backlight issues, help wanted
From: Hans de Goede @ 2026-05-05 9:52 UTC (permalink / raw)
To: Lee Jones, Daniel Thompson, Jingoo Han, Helge Deller,
Daniel Dadap, Rafael J. Wysocki
Cc: dri-devel@lists.freedesktop.org, linux-fbdev, linux-acpi,
platform-driver-x86@vger.kernel.org
<resend adding pdx86 list, sorry>
Hi All,
A while ago Nvidia introduced a new Nvidia specific firmware method
for controlling the backlight on laptops with runtime switchable
Nvidia hybrid graphics.
This is supported through the nvidia-wmi-ec-backlight driver, but has
never worked 100%.
The new WMI firmware interface has a method to ask the firmware if
the backlight is controlled though the EC and this the new WMI interface
should be used; or if it is directly controlled by the GPU and the GPU
driver's native backlight support should be used.
There are several bugs in the implementation of this on various laptops:
1. The method to get the backlight control source sometimes does not
report the correct value.
2. On some laptop models which method (native-gpu vs nvidia-wmi) works
changes at runtime, e.g. when plugging in a charger.
Known affected laptop models/bug reports about this:
- Acer Predator PH315-55: needs acpi_backlight=native
- Dell G15 5515 with RTX 3050: *needs* acpi_backlight=native
- Dell G15 5515 with RTX 3060: *breaks* with acpi_backlight=native
- Lenovo Legion Slim 7 2021
- https://bugzilla.kernel.org/show_bug.cgi?id=217026
- https://gitlab.gnome.org/GNOME/gnome-settings-daemon/-/work_items/784
- https://gitlab.freedesktop.org/drm/amd/-/issues/4512
- https://bugzilla.suse.com/show_bug.cgi?id=1217750
It turns out that under Windows both a WMI backlight driver and a GPU
native backlight driver get installed and Windows simply always calls
both when the backlight changes working around these kind of firmware
bugs.
When this first came up, about 2 years ago, I came up with the below
plan to fix this. Nvidia was supposed to work in implementing this,
but so far an implementation of this plan has not happened.
Note I do not have time to work on this myself. I'm posting this here
in the hope that either Nvidia will pick this up after all; or that
someone else can make this happen.
I'm more then happy to help answering any questions which may come up
while implementing this; and to review the resulting patches.
The plan
========
1. Modify the core backlight code to allow registering a backlight-device
for in kernel use only, disabling the registering of a class device under
/sys/class/backlight .
2. Add a new backlight-aggregate.c backlight driver, which exports a
devm_backlight_aggregate_register_or_add() function. Drivers can call
this passing in an existing backlight-device (with its sysfs interface
disabled). This either creates a singleton /sys/class/backlight/aggregate
device, or adds the passed in backlight to the existing singleton instance
if it already exists.
This new driver always exposes a range of 0-255 to userspace. This acts
as a proxie for any backlight-devices registered to be part of
the aggregate, forwarding any brightness set calls to all backlights,
scaled to their actual range. For reads this will report the last set
brightness value (starting with the value of the first registered
backlight-device).
3. Add a new nvidia_wmi_ec_and_native type to drivers/acpi/video_detect.c
for both DMI quirks and commandline handling.
4. Modify acpi_video_backlight_use_native() to also return true if
the __acpi_video_get_backlight_type() call there returns the new
acpi_backlight_nvidia_wmi_ec_and_native.
5. Add a new devm_backlight_device_register_native() helper which
calls __acpi_video_get_backlight_type(true, NULL) and if that returns
the new nvidia_wmi_ec_and_native type then registers the passed in
backlight with the flag to not register a sysfs class interface and
then on success calls the new devm_backlight_aggregate_register_or_add()
with the just registered backlight device; and if the returned type
instead is acpi_backlight_native register the passed in backlight
normally through devm_backlight_device_register()
5. Modify the i915 and amdgpu drivers to use the new
devm_backlight_device_register_native() helper. Since this new helper
checks the backlight-type itself, drop acpi_video_backlight_use_native()
checks *if* the registration is the only thing guarded by that check.
6. drivers/platform/x86/nvidia-wmi-ec-backlight.c to not return
early from probe when acpi_video_get_backlight_type() returns
the new nvidia_wmi_ec_and_native type and for that type make it
registers its backlight with the flag to not register a sysfs class
interface and then on success calls the new
devm_backlight_aggregate_register_or_add().
Regards,
Hans
^ permalink raw reply
* Re: [PATCH v1] fbdev/offb: fix PCI device reference leak on probe failure
From: Helge Deller @ 2026-05-05 10:10 UTC (permalink / raw)
To: dbgh9129, Jason, linux-fbdev
Cc: dri-devel, linux-kernel, mhun512, ae878000, tmk5904
In-Reply-To: <CACrCO_VZg_2PXG011qQ7NWo3iz-u2HE6DdHZWQdQ_UnRk4A0Eg@mail.gmail.com>
On 5/5/26 03:39, dbgh9129@gmail.com wrote:
> I am sending a gentle ping on this patch. Please let me know if you
> have any feedback or if any changes are required.
Both of your patches (offb and savagefb) were merged upstream 13 days ago:
https://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev.git/log/?h=fbdev-7.1-2
Usually I send "patch applied" messages, but in this case I probably forgot.
Helge
^ permalink raw reply
* Re: [PATCH v1] fbdev/offb: fix PCI device reference leak on probe failure
From: 최유호 @ 2026-05-05 11:22 UTC (permalink / raw)
To: Helge Deller
Cc: Jason, linux-fbdev, dri-devel, linux-kernel, mhun512, ae878000,
tmk5904
In-Reply-To: <2bf485cd-0c6d-4f0e-99d6-7b592b949a1f@gmx.de>
Dear Helge,
Thanks for letting me know that the patches were merged.
Best regards,
Yuho Choi
On Tue, 5 May 2026 at 06:10, Helge Deller <deller@gmx.de> wrote:
>
> On 5/5/26 03:39, dbgh9129@gmail.com wrote:
> > I am sending a gentle ping on this patch. Please let me know if you
> > have any feedback or if any changes are required.
>
> Both of your patches (offb and savagefb) were merged upstream 13 days ago:
> https://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev.git/log/?h=fbdev-7.1-2
>
> Usually I send "patch applied" messages, but in this case I probably forgot.
>
> Helge
^ permalink raw reply
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