/*
* The order of these masks is important. Matching masks will be seen
* first and the left over flags will end up showing by themselves.
*
* For example, if we have GFP_KERNEL before GFP_USER we wil get:
*
* GFP_KERNEL|GFP_HARDWALL
*
* Thus most bits set go first.
*/
#define __def_gfpflag_names \
{(unsigned long)GFP_TRANSHUGE, "GFP_TRANSHUGE"}, \
{(unsigned long)GFP_TRANSHUGE_LIGHT, "GFP_TRANSHUGE_LIGHT"}, \
{(unsigned long)GFP_HIGHUSER_MOVABLE, "GFP_HIGHUSER_MOVABLE"},\
{(unsigned long)GFP_HIGHUSER, "GFP_HIGHUSER"}, \
{(unsigned long)GFP_USER, "GFP_USER"}, \
{(unsigned long)GFP_TEMPORARY, "GFP_TEMPORARY"}, \
{(unsigned long)GFP_KERNEL_ACCOUNT, "GFP_KERNEL_ACCOUNT"}, \
{(unsigned long)GFP_KERNEL, "GFP_KERNEL"}, \
{(unsigned long)GFP_NOFS, "GFP_NOFS"}, \
{(unsigned long)GFP_ATOMIC, "GFP_ATOMIC"}, \
{(unsigned long)GFP_NOIO, "GFP_NOIO"}, \
{(unsigned long)GFP_NOWAIT, "GFP_NOWAIT"}, \
{(unsigned long)GFP_DMA, "GFP_DMA"}, \
{(unsigned long)__GFP_HIGHMEM, "__GFP_HIGHMEM"}, \
{(unsigned long)GFP_DMA32, "GFP_DMA32"}, \
{(unsigned long)__GFP_HIGH, "__GFP_HIGH"}, \
{(unsigned long)__GFP_ATOMIC, "__GFP_ATOMIC"}, \
{(unsigned long)__GFP_IO, "__GFP_IO"}, \
{(unsigned long)__GFP_FS, "__GFP_FS"}, \
{(unsigned long)__GFP_COLD, "__GFP_COLD"}, \
{(unsigned long)__GFP_NOWARN, "__GFP_NOWARN"}, \
{(unsigned long)__GFP_REPEAT, "__GFP_REPEAT"}, \
{(unsigned long)__GFP_NOFAIL, "__GFP_NOFAIL"}, \
{(unsigned long)__GFP_NORETRY, "__GFP_NORETRY"}, \
{(unsigned long)__GFP_COMP, "__GFP_COMP"}, \
{(unsigned long)__GFP_ZERO, "__GFP_ZERO"}, \
{(unsigned long)__GFP_NOMEMALLOC, "__GFP_NOMEMALLOC"}, \
{(unsigned long)__GFP_MEMALLOC, "__GFP_MEMALLOC"}, \
{(unsigned long)__GFP_HARDWALL, "__GFP_HARDWALL"}, \
{(unsigned long)__GFP_THISNODE, "__GFP_THISNODE"}, \
{(unsigned long)__GFP_RECLAIMABLE, "__GFP_RECLAIMABLE"}, \
{(unsigned long)__GFP_MOVABLE, "__GFP_MOVABLE"}, \
{(unsigned long)__GFP_ACCOUNT, "__GFP_ACCOUNT"}, \
{(unsigned long)__GFP_NOTRACK, "__GFP_NOTRACK"}, \
{(unsigned long)__GFP_WRITE, "__GFP_WRITE"}, \
{(unsigned long)__GFP_RECLAIM, "__GFP_RECLAIM"}, \
{(unsigned long)__GFP_DIRECT_RECLAIM, "__GFP_DIRECT_RECLAIM"},\
{(unsigned long)__GFP_KSWAPD_RECLAIM, "__GFP_KSWAPD_RECLAIM"}\
#define show_gfp_flags(flags) \
(flags) ? __print_flags(flags, "|", \
__def_gfpflag_names \
) : "none"
#ifdef CONFIG_MMU
#define IF_HAVE_PG_MLOCK(flag,string) ,{1UL << flag, string}
#else
#define IF_HAVE_PG_MLOCK(flag,string)
#endif
#ifdef CONFIG_ARCH_USES_PG_UNCACHED
#define IF_HAVE_PG_UNCACHED(flag,string) ,{1UL << flag, string}
#else
#define IF_HAVE_PG_UNCACHED(flag,string)
#endif
#ifdef CONFIG_MEMORY_FAILURE
#define IF_HAVE_PG_HWPOISON(flag,string) ,{1UL << flag, string}
#else
#define IF_HAVE_PG_HWPOISON(flag,string)
#endif
#if defined(CONFIG_IDLE_PAGE_TRACKING) && defined(CONFIG_64BIT)
#define IF_HAVE_PG_IDLE(flag,string) ,{1UL << flag, string}
#else
#define IF_HAVE_PG_IDLE(flag,string)
#endif
#define __def_pageflag_names \
{1UL << PG_locked, "locked" }, \
{1UL << PG_waiters, "waiters" }, \
{1UL << PG_error, "error" }, \
{1UL << PG_referenced, "referenced" }, \
{1UL << PG_uptodate, "uptodate" }, \
{1UL << PG_dirty, "dirty" }, \
{1UL << PG_lru, "lru" }, \
{1UL << PG_active, "active" }, \
{1UL << PG_slab, "slab" }, \
{1UL << PG_owner_priv_1, "owner_priv_1" }, \
{1UL << PG_arch_1, "arch_1" }, \
{1UL << PG_reserved, "reserved" }, \
{1UL << PG_private, "private" }, \
{1UL << PG_private_2, "private_2" }, \
{1UL << PG_writeback, "writeback" }, \
{1UL << PG_head, "head" }, \
{1UL << PG_mappedtodisk, "mappedtodisk" }, \
{1UL << PG_reclaim, "reclaim" }, \
{1UL << PG_swapbacked, "swapbacked" }, \
{1UL << PG_unevictable, "unevictable" } \
IF_HAVE_PG_MLOCK(PG_mlocked, "mlocked" ) \
IF_HAVE_PG_UNCACHED(PG_uncached, "uncached" ) \
IF_HAVE_PG_HWPOISON(PG_hwpoison, "hwpoison" ) \
IF_HAVE_PG_IDLE(PG_young, "young" ) \
IF_HAVE_PG_IDLE(PG_idle, "idle" )
#define show_page_flags(flags) \
(flags) ? __print_flags(flags, "|", \
__def_pageflag_names \
) : "none"
#if defined(CONFIG_X86)
#define __VM_ARCH_SPECIFIC_1 {VM_PAT, "pat" }
#elif defined(CONFIG_PPC)
#define __VM_ARCH_SPECIFIC_1 {VM_SAO, "sao" }
#elif defined(CONFIG_PARISC) || defined(CONFIG_METAG) || defined(CONFIG_IA64)
#define __VM_ARCH_SPECIFIC_1 {VM_GROWSUP, "growsup" }
#elif !defined(CONFIG_MMU)
#define __VM_ARCH_SPECIFIC_1 {VM_MAPPED_COPY,"mappedcopy" }
#else
#define __VM_ARCH_SPECIFIC_1 {VM_ARCH_1, "arch_1" }
#endif
#if defined(CONFIG_X86)
#define __VM_ARCH_SPECIFIC_2 {VM_MPX, "mpx" }
#else
#define __VM_ARCH_SPECIFIC_2 {VM_ARCH_2, "arch_2" }
#endif
#ifdef CONFIG_MEM_SOFT_DIRTY
#define IF_HAVE_VM_SOFTDIRTY(flag,name) {flag, name },
#else
#define IF_HAVE_VM_SOFTDIRTY(flag,name)
#endif
#define __def_vmaflag_names \
{VM_READ, "read" }, \
{VM_WRITE, "write" }, \
{VM_EXEC, "exec" }, \
{VM_SHARED, "shared" }, \
{VM_MAYREAD, "mayread" }, \
{VM_MAYWRITE, "maywrite" }, \
{VM_MAYEXEC, "mayexec" }, \
{VM_MAYSHARE, "mayshare" }, \
{VM_GROWSDOWN, "growsdown" }, \
{VM_UFFD_MISSING, "uffd_missing" }, \
{VM_PFNMAP, "pfnmap" }, \
{VM_DENYWRITE, "denywrite" }, \
{VM_UFFD_WP, "uffd_wp" }, \
{VM_LOCKED, "locked" }, \
{VM_IO, "io" }, \
{VM_SEQ_READ, "seqread" }, \
{VM_RAND_READ, "randread" }, \
{VM_DONTCOPY, "dontcopy" }, \
{VM_DONTEXPAND, "dontexpand" }, \
{VM_LOCKONFAULT, "lockonfault" }, \
{VM_ACCOUNT, "account" }, \
{VM_NORESERVE, "noreserve" }, \
{VM_HUGETLB, "hugetlb" }, \
__VM_ARCH_SPECIFIC_1 , \
__VM_ARCH_SPECIFIC_2 , \
{VM_DONTDUMP, "dontdump" }, \
IF_HAVE_VM_SOFTDIRTY(VM_SOFTDIRTY, "softdirty" ) \
{VM_MIXEDMAP, "mixedmap" }, \
{VM_HUGEPAGE, "hugepage" }, \
{VM_NOHUGEPAGE, "nohugepage" }, \
{VM_MERGEABLE, "mergeable" } \
#define show_vma_flags(flags) \
(flags) ? __print_flags(flags, "|", \
__def_vmaflag_names \
) : "none"
d) call to i915_vma_unpin_fence()
tries to dereference it.
It seems to be some race condition where the object is going away at
shutdown time, since both times happened when shutting down the X
server. The call chains were different:
- VT ioctl(KDSETMODE, KD_TEXT):
intel_cleanup_plane_fb+0x5b/0xa0 [i915]
drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper]
intel_atomic_commit_tail+0x749/0xfe0 [i915]
intel_atomic_commit+0x3cb/0x4f0 [i915]
drm_atomic_commit+0x4b/0x50 [drm]
restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper]
drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper]
drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper]
intel_fbdev_set_par+0x18/0x70 [i915]
fb_set_var+0x236/0x460
fbcon_blank+0x30f/0x350
do_unblank_screen+0xd2/0x1a0
vt_ioctl+0x507/0x12a0
tty_ioctl+0x355/0xc30
do_vfs_ioctl+0xa3/0x5e0
SyS_ioctl+0x79/0x90
entry_SYSCALL_64_fastpath+0x13/0x94
- i915 unpin_work workqueue:
intel_unpin_work_fn+0x58/0x140 [i915]
process_one_work+0x1f1/0x480
worker_thread+0x48/0x4d0
kthread+0x101/0x140
and this patch purely papers over the issue by adding a NULL pointer
check and a WARN_ON_ONCE() to avoid the oops that would then generally
make the machine unresponsive.
Other callers of i915_gem_object_to_ggtt() seem to also check for the
returned pointer being NULL and warn about it, so this clearly has
happened before in other places.
[ Reported it originally to the i915 developers on Jan 8, applying the
ugly workaround on my own now after triggering the problem for the
second time with no feedback.
This is likely to be the same bug reported as
https://bugs.freedesktop.org/show_bug.cgi?id=98829
https://bugs.freedesktop.org/show_bug.cgi?id=99134
which has a patch for the underlying problem, but it hasn't gotten to
me, so I'm applying the workaround. ]
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>