From: kernel test robot <lkp@intel.com>
To: Maarten Lankhorst <dev@lankhorst.se>, intel-xe@lists.freedesktop.org
Cc: oe-kbuild-all@lists.linux.dev, intel-gfx@lists.freedesktop.org
Subject: Re: [i915-rt v2 06/16] drm/i915/display: Remove locking from intel_vblank_evade critical section
Date: Mon, 22 Dec 2025 19:14:08 +0100 [thread overview]
Message-ID: <202512221945.2ncUer0c-lkp@intel.com> (raw)
In-Reply-To: <20251216092226.1777909-24-dev@lankhorst.se>
Hi Maarten,
kernel test robot noticed the following build errors:
[auto build test ERROR on drm-i915/for-linux-next]
[also build test ERROR on drm-i915/for-linux-next-fixes drm-xe/drm-xe-next drm-tip/drm-tip next-20251219]
[cannot apply to linus/master v6.16-rc1]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Maarten-Lankhorst/drm-i915-display-Fix-intel_lpe_audio_irq_handler-for-PREEMPT-RT/20251216-212722
base: https://gitlab.freedesktop.org/drm/i915/kernel.git for-linux-next
patch link: https://lore.kernel.org/r/20251216092226.1777909-24-dev%40lankhorst.se
patch subject: [i915-rt v2 06/16] drm/i915/display: Remove locking from intel_vblank_evade critical section
config: x86_64-rhel-9.4-ltp (https://download.01.org/0day-ci/archive/20251222/202512221945.2ncUer0c-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251222/202512221945.2ncUer0c-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/202512221945.2ncUer0c-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/gpu/drm/i915/display/intel_vblank.c:245:12: error: static declaration of '__intel_get_crtc_scanline' follows non-static declaration
245 | static int __intel_get_crtc_scanline(struct intel_crtc *crtc)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/gpu/drm/i915/display/intel_vblank.c:19:
drivers/gpu/drm/i915/display/intel_vblank.h:41:5: note: previous declaration of '__intel_get_crtc_scanline' with type 'int(struct intel_crtc *)'
41 | int __intel_get_crtc_scanline(struct intel_crtc *crtc);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/i915/display/intel_vblank.c: In function 'scanline_in_safe_range':
drivers/gpu/drm/i915/display/intel_vblank.c:716:17: error: implicit declaration of function 'intel_vblank_section_enter_irqf'; did you mean 'intel_vblank_section_enter'? [-Wimplicit-function-declaration]
716 | intel_vblank_section_enter_irqf(display, &irqflags);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| intel_vblank_section_enter
>> drivers/gpu/drm/i915/display/intel_vblank.c:716:49: error: 'display' undeclared (first use in this function)
716 | intel_vblank_section_enter_irqf(display, &irqflags);
| ^~~~~~~
drivers/gpu/drm/i915/display/intel_vblank.c:716:49: note: each undeclared identifier is reported only once for each function it appears in
>> drivers/gpu/drm/i915/display/intel_vblank.c:718:9: error: 'position' undeclared (first use in this function)
718 | position = __intel_get_crtc_scanline(crtc);
| ^~~~~~~~
>> drivers/gpu/drm/i915/display/intel_vblank.c:718:46: error: 'crtc' undeclared (first use in this function)
718 | position = __intel_get_crtc_scanline(crtc);
| ^~~~
drivers/gpu/drm/i915/display/intel_vblank.c:721:17: error: implicit declaration of function 'intel_vblank_section_exit_irqf'; did you mean 'intel_vblank_section_exit'? [-Wimplicit-function-declaration]
721 | intel_vblank_section_exit_irqf(display, irqflags);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| intel_vblank_section_exit
vim +/__intel_get_crtc_scanline +245 drivers/gpu/drm/i915/display/intel_vblank.c
5b7f65acf1b083 Ville Syrjälä 2024-05-28 240
62fe4515cf2027 Jani Nikula 2023-01-16 241 /*
62fe4515cf2027 Jani Nikula 2023-01-16 242 * intel_de_read_fw(), only for fast reads of display block, no need for
62fe4515cf2027 Jani Nikula 2023-01-16 243 * forcewake etc.
62fe4515cf2027 Jani Nikula 2023-01-16 244 */
62fe4515cf2027 Jani Nikula 2023-01-16 @245 static int __intel_get_crtc_scanline(struct intel_crtc *crtc)
62fe4515cf2027 Jani Nikula 2023-01-16 246 {
aa451ae76fda24 Jani Nikula 2024-08-22 247 struct intel_display *display = to_intel_display(crtc);
0097ecd06d9dcf Ville Syrjälä 2024-04-08 248 struct drm_vblank_crtc *vblank = drm_crtc_vblank_crtc(&crtc->base);
0097ecd06d9dcf Ville Syrjälä 2024-04-08 249 const struct drm_display_mode *mode = &vblank->hwmode;
62fe4515cf2027 Jani Nikula 2023-01-16 250 enum pipe pipe = crtc->pipe;
62fe4515cf2027 Jani Nikula 2023-01-16 251 int position, vtotal;
62fe4515cf2027 Jani Nikula 2023-01-16 252
62fe4515cf2027 Jani Nikula 2023-01-16 253 if (!crtc->active)
62fe4515cf2027 Jani Nikula 2023-01-16 254 return 0;
62fe4515cf2027 Jani Nikula 2023-01-16 255
62fe4515cf2027 Jani Nikula 2023-01-16 256 if (crtc->mode_flags & I915_MODE_FLAG_GET_SCANLINE_FROM_TIMESTAMP)
62fe4515cf2027 Jani Nikula 2023-01-16 257 return __intel_get_crtc_scanline_from_timestamp(crtc);
62fe4515cf2027 Jani Nikula 2023-01-16 258
9677dd01ca1ada Ville Syrjälä 2024-05-28 259 vtotal = intel_mode_vtotal(mode);
62fe4515cf2027 Jani Nikula 2023-01-16 260
aa451ae76fda24 Jani Nikula 2024-08-22 261 position = intel_de_read_fw(display, PIPEDSL(display, pipe)) & PIPEDSL_LINE_MASK;
62fe4515cf2027 Jani Nikula 2023-01-16 262
62fe4515cf2027 Jani Nikula 2023-01-16 263 /*
62fe4515cf2027 Jani Nikula 2023-01-16 264 * On HSW, the DSL reg (0x70000) appears to return 0 if we
62fe4515cf2027 Jani Nikula 2023-01-16 265 * read it just before the start of vblank. So try it again
62fe4515cf2027 Jani Nikula 2023-01-16 266 * so we don't accidentally end up spanning a vblank frame
62fe4515cf2027 Jani Nikula 2023-01-16 267 * increment, causing the pipe_update_end() code to squak at us.
62fe4515cf2027 Jani Nikula 2023-01-16 268 *
62fe4515cf2027 Jani Nikula 2023-01-16 269 * The nature of this problem means we can't simply check the ISR
62fe4515cf2027 Jani Nikula 2023-01-16 270 * bit and return the vblank start value; nor can we use the scanline
62fe4515cf2027 Jani Nikula 2023-01-16 271 * debug register in the transcoder as it appears to have the same
62fe4515cf2027 Jani Nikula 2023-01-16 272 * problem. We may need to extend this to include other platforms,
62fe4515cf2027 Jani Nikula 2023-01-16 273 * but so far testing only shows the problem on HSW.
62fe4515cf2027 Jani Nikula 2023-01-16 274 */
aa451ae76fda24 Jani Nikula 2024-08-22 275 if (HAS_DDI(display) && !position) {
62fe4515cf2027 Jani Nikula 2023-01-16 276 int i, temp;
62fe4515cf2027 Jani Nikula 2023-01-16 277
62fe4515cf2027 Jani Nikula 2023-01-16 278 for (i = 0; i < 100; i++) {
62fe4515cf2027 Jani Nikula 2023-01-16 279 udelay(1);
aa451ae76fda24 Jani Nikula 2024-08-22 280 temp = intel_de_read_fw(display,
aa451ae76fda24 Jani Nikula 2024-08-22 281 PIPEDSL(display, pipe)) & PIPEDSL_LINE_MASK;
62fe4515cf2027 Jani Nikula 2023-01-16 282 if (temp != position) {
62fe4515cf2027 Jani Nikula 2023-01-16 283 position = temp;
62fe4515cf2027 Jani Nikula 2023-01-16 284 break;
62fe4515cf2027 Jani Nikula 2023-01-16 285 }
62fe4515cf2027 Jani Nikula 2023-01-16 286 }
62fe4515cf2027 Jani Nikula 2023-01-16 287 }
62fe4515cf2027 Jani Nikula 2023-01-16 288
62fe4515cf2027 Jani Nikula 2023-01-16 289 /*
62fe4515cf2027 Jani Nikula 2023-01-16 290 * See update_scanline_offset() for the details on the
62fe4515cf2027 Jani Nikula 2023-01-16 291 * scanline_offset adjustment.
62fe4515cf2027 Jani Nikula 2023-01-16 292 */
5316dd0d617bb9 Ville Syrjälä 2024-05-28 293 return (position + vtotal + crtc->scanline_offset) % vtotal;
62fe4515cf2027 Jani Nikula 2023-01-16 294 }
62fe4515cf2027 Jani Nikula 2023-01-16 295
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
next prev parent reply other threads:[~2025-12-22 18:14 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-16 9:22 [i915-rt v2 00/16] drm/i915/display: All patches to make PREEMPT_RT work on i915 + xe Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 01/16] drm/i915/display: Fix intel_lpe_audio_irq_handler for PREEMPT-RT Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 02/16] drm/i915/display: Make get_vblank_counter use intel_de_read_fw() Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 03/16] drm/i915/display: Use intel_de_write_fw in intel_pipe_fastset Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 04/16] drm/i915/display: Make set_pipeconf use the fw variants Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 05/16] drm/i915/display: Move vblank put until after critical section Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 06/16] drm/i915/display: Remove locking from intel_vblank_evade " Maarten Lankhorst
2025-12-16 20:15 ` [i915-rt v2.1] " Maarten Lankhorst
2025-12-22 18:14 ` kernel test robot [this message]
2025-12-16 9:22 ` [i915-rt v2 07/16] drm/i915/display: Handle vlv dsi workaround in scanline_in_safe_range too Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 08/16] drm/i915/display: Make icl_dsi_frame_update use _fw too Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 09/16] drm/i915/display: Enable interrupts earlier on PREEMPT_RT Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 10/16] drm/i915: Use preempt_disable/enable_rt() where recommended Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 11/16] PREEMPT_RT injection Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 12/16] drm/i915/display: Use intel_de_read_fw in colorops Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 13/16] drm/i915/gt: Use spin_lock_irq() instead of local_irq_disable() + spin_lock() Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 14/16] drm/i915: Drop the irqs_disabled() check Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 15/16] drm/i915/guc: Consider also RCU depth in busy loop Maarten Lankhorst
2025-12-16 9:22 ` [i915-rt v2 16/16] Revert "drm/i915: Depend on !PREEMPT_RT." Maarten Lankhorst
2025-12-16 13:51 ` ✗ CI.checkpatch: warning for drm/i915/display: All patches to make PREEMPT_RT work on i915 + xe. (rev2) Patchwork
2025-12-16 13:52 ` ✓ CI.KUnit: success " Patchwork
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