Re: [PATCH v17 10/18] drm/shmem-helper: Use refcount_t for vmap_use_count

[kernel test robot <oliver.sang@intel.com>]

Hello,

kernel test robot noticed "WARNING:at_drivers/gpu/drm/drm_fbdev_generic.c:#drm_fbdev_generic_helper_fb_dirty" on:

commit: e5f31d1a2da5d43187a0e1fc4d1882982ab0d9b8 ("[PATCH v17 10/18] drm/shmem-helper: Use refcount_t for vmap_use_count")
url: https://github.com/intel-lab-lkp/linux/commits/Dmitry-Osipenko/drm-gem-Change-locked-unlocked-postfix-of-drm_gem_v-unmap-function-names/20230915-073105
base: git://anongit.freedesktop.org/drm/drm drm-next
patch link: https://lore.kernel.org/all/20230914232721.408581-11-dmitry.osipenko@collabora.com/
patch subject: [PATCH v17 10/18] drm/shmem-helper: Use refcount_t for vmap_use_count

in testcase: rcuscale
version: 
with following parameters:

	runtime: 300s
	scale_type: tasks



compiler: gcc-11
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G

(please refer to attached dmesg/kmsg for entire log/backtrace)



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 <oliver.sang@intel.com>
| Closes: https://lore.kernel.org/oe-lkp/202309261238.bce3ce91-oliver.sang@intel.com


[   23.102568][    T8] ------------[ cut here ]------------
[   23.102576][    T8] platform vkms: Damage blitter failed: ret=-12
[ 23.102605][ T8] WARNING: CPU: 0 PID: 8 at drivers/gpu/drm/drm_fbdev_generic.c:226 drm_fbdev_generic_helper_fb_dirty (drivers/gpu/drm/drm_fbdev_generic.c:226) 
[   23.102614][    T8] Modules linked in:
[   23.102619][    T8] CPU: 0 PID: 8 Comm: kworker/0:0 Tainted: G                 N 6.6.0-rc1-00010-ge5f31d1a2da5 #1 debbcfa26ac7594ab4e1fde44696b4efa3ea485a
[   23.102624][    T8] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
[   23.102627][    T8] Workqueue: events drm_fb_helper_damage_work
[ 23.102631][ T8] EIP: drm_fbdev_generic_helper_fb_dirty (drivers/gpu/drm/drm_fbdev_generic.c:226) 
[ 23.102633][ T8] Code: 05 a8 49 81 c2 01 8b 40 08 8b 58 2c 85 db 75 02 8b 18 89 55 e0 e8 90 7a 04 00 8b 55 e0 52 53 50 68 d4 41 28 c2 e8 74 68 a5 ff <0f> 0b 8b 55 e0 83 c4 10 e9 7b ff ff ff 8d 76 00 8b 45 e4 8b 55 e8
All code
========
   0:	05 a8 49 81 c2       	add    $0xc28149a8,%eax
   5:	01 8b 40 08 8b 58    	add    %ecx,0x588b0840(%rbx)
   b:	2c 85                	sub    $0x85,%al
   d:	db 75 02             	(bad)  0x2(%rbp)
  10:	8b 18                	mov    (%rax),%ebx
  12:	89 55 e0             	mov    %edx,-0x20(%rbp)
  15:	e8 90 7a 04 00       	call   0x47aaa
  1a:	8b 55 e0             	mov    -0x20(%rbp),%edx
  1d:	52                   	push   %rdx
  1e:	53                   	push   %rbx
  1f:	50                   	push   %rax
  20:	68 d4 41 28 c2       	push   $0xffffffffc22841d4
  25:	e8 74 68 a5 ff       	call   0xffffffffffa5689e
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	8b 55 e0             	mov    -0x20(%rbp),%edx
  2f:	83 c4 10             	add    $0x10,%esp
  32:	e9 7b ff ff ff       	jmp    0xffffffffffffffb2
  37:	8d 76 00             	lea    0x0(%rsi),%esi
  3a:	8b 45 e4             	mov    -0x1c(%rbp),%eax
  3d:	8b 55 e8             	mov    -0x18(%rbp),%edx

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	8b 55 e0             	mov    -0x20(%rbp),%edx
   5:	83 c4 10             	add    $0x10,%esp
   8:	e9 7b ff ff ff       	jmp    0xffffffffffffff88
   d:	8d 76 00             	lea    0x0(%rsi),%esi
  10:	8b 45 e4             	mov    -0x1c(%rbp),%eax
  13:	8b 55 e8             	mov    -0x18(%rbp),%edx
[   23.102636][    T8] EAX: 00000000 EBX: ee027ab0 ECX: 00000000 EDX: 00000000
[   23.102638][    T8] ESI: c624b600 EDI: c624b738 EBP: c3585ef8 ESP: c3585ec4
[   23.102640][    T8] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010246
[   23.102647][    T8] CR0: 80050033 CR2: ffd3a000 CR3: 0295e000 CR4: 00040690
[   23.102649][    T8] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
[   23.102651][    T8] DR6: fffe0ff0 DR7: 00000400
[   23.102653][    T8] Call Trace:
[ 23.102656][ T8] ? show_regs (arch/x86/kernel/dumpstack.c:479 arch/x86/kernel/dumpstack.c:465) 
[ 23.102661][ T8] ? drm_fbdev_generic_helper_fb_dirty (drivers/gpu/drm/drm_fbdev_generic.c:226) 
[ 23.102664][ T8] ? __warn (kernel/panic.c:673) 
[ 23.102668][ T8] ? drm_fbdev_generic_helper_fb_dirty (drivers/gpu/drm/drm_fbdev_generic.c:226) 
[ 23.102670][ T8] ? report_bug (lib/bug.c:201 lib/bug.c:219) 
[ 23.102677][ T8] ? exc_overflow (arch/x86/kernel/traps.c:250) 
[ 23.102681][ T8] ? handle_bug (arch/x86/kernel/traps.c:216) 
[ 23.102685][ T8] ? exc_invalid_op (arch/x86/kernel/traps.c:258 (discriminator 1)) 
[ 23.102689][ T8] ? handle_exception (arch/x86/entry/entry_32.S:1056) 
[ 23.102701][ T8] ? exc_overflow (arch/x86/kernel/traps.c:250) 
[ 23.102704][ T8] ? drm_fbdev_generic_helper_fb_dirty (drivers/gpu/drm/drm_fbdev_generic.c:226) 
[ 23.102708][ T8] ? exc_overflow (arch/x86/kernel/traps.c:250) 
[ 23.102710][ T8] ? drm_fbdev_generic_helper_fb_dirty (drivers/gpu/drm/drm_fbdev_generic.c:226) 
[ 23.102715][ T8] ? trace_hardirqs_on (kernel/trace/trace_preemptirq.c:63) 
[ 23.102720][ T8] drm_fb_helper_damage_work (drivers/gpu/drm/drm_fb_helper.c:391 drivers/gpu/drm/drm_fb_helper.c:413) 
[ 23.102723][ T8] process_one_work (kernel/workqueue.c:2635) 
[ 23.102731][ T8] worker_thread (kernel/workqueue.c:2697 kernel/workqueue.c:2784) 
[ 23.102736][ T8] kthread (kernel/kthread.c:388) 
[ 23.102740][ T8] ? process_one_work (kernel/workqueue.c:2730) 
[ 23.102743][ T8] ? kthread_complete_and_exit (kernel/kthread.c:341) 
[ 23.102747][ T8] ret_from_fork (arch/x86/kernel/process.c:153) 
[ 23.102750][ T8] ? kthread_complete_and_exit (kernel/kthread.c:341) 
[ 23.102754][ T8] ret_from_fork_asm (arch/x86/entry/entry_32.S:741) 
[ 23.102757][ T8] entry_INT80_32 (arch/x86/entry/entry_32.S:947) 
[   23.102765][    T8] irq event stamp: 249311
[ 23.102767][ T8] hardirqs last enabled at (249317): vprintk_emit (arch/x86/include/asm/irqflags.h:42 arch/x86/include/asm/irqflags.h:77 arch/x86/include/asm/irqflags.h:135 kernel/printk/printk.c:1961 kernel/printk/printk.c:2306) 
[ 23.102772][ T8] hardirqs last disabled at (249322): vprintk_emit (kernel/printk/printk.c:1940 kernel/printk/printk.c:2306) 
[ 23.102775][ T8] softirqs last enabled at (235498): __do_softirq (arch/x86/include/asm/preempt.h:27 kernel/softirq.c:400 kernel/softirq.c:582) 
[ 23.102778][ T8] softirqs last disabled at (235491): do_softirq_own_stack (arch/x86/kernel/irq_32.c:57 arch/x86/kernel/irq_32.c:147) 
[   23.102781][    T8] ---[ end trace 0000000000000000 ]---
[   23.104064][    T1] Console: switching to colour frame buffer device 128x48
[   23.189012][    T1] platform vkms: [drm] fb0: vkmsdrmfb frame buffer device



The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20230926/202309261238.bce3ce91-oliver.sang@intel.com



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0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki