drm: qxl: Delay entering atomic context during cursor update
authorGabriel Krisman Bertazi <krisman@collabora.co.uk>
Fri, 19 May 2017 17:58:19 +0000 (14:58 -0300)
committerGerd Hoffmann <kraxel@redhat.com>
Tue, 23 May 2017 07:17:04 +0000 (09:17 +0200)
commit429030bc944ee9a8bbe5d9bb23dcda0ae2205450
tree0ee630a1e90a6e3fa3299fa3cc4cebcc2f8ea2a7
parente480eabae232b92ff44ce63678280373713920a4
drm: qxl: Delay entering atomic context during cursor update

qxl_release_map will enter an atomic context, but since we still need to
alloc memory for BOs, we better delay that until we have everything we
need, in case we need to sleep inside the allocation.  This avoids the
Sleep in atomic state below, which was reported by Mike.

 [   43.910362] BUG: sleeping function called from invalid context at mm/slab.h:432
 [   43.910955] in_atomic(): 1, irqs_disabled(): 0, pid: 2077, name: Xorg
 [   43.911472] Preemption disabled at:
 [   43.911478] [<ffffffffa02b1c45>] qxl_bo_kmap_atomic_page+0xa5/0x100 [qxl]
 [   43.912103] CPU: 0 PID: 2077 Comm: Xorg Tainted: G            E   4.12.0-master #38
 [ 43.912550] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
 rel-1.8.1-0-g4adadbd-20161202_174313-build11a 04/01/2014
 [   43.913202] Call Trace:
 [   43.913371]  dump_stack+0x65/0x89
 [   43.913581]  ? qxl_bo_kmap_atomic_page+0xa5/0x100 [qxl]
 [   43.913876]  ___might_sleep+0x11a/0x190
 [   43.914095]  __might_sleep+0x4a/0x80
 [   43.914319]  ? qxl_bo_create+0x50/0x190 [qxl]
 [   43.914565]  kmem_cache_alloc_trace+0x46/0x180
 [   43.914836]  qxl_bo_create+0x50/0x190 [qxl]
 [   43.915082]  ? refcount_dec_and_test+0x11/0x20
 [   43.915332]  ? ttm_mem_io_reserve+0x41/0xe0 [ttm]
 [   43.915595]  qxl_alloc_bo_reserved+0x37/0xb0 [qxl]
 [   43.915884]  qxl_cursor_atomic_update+0x8f/0x260 [qxl]
 [   43.916172]  ? drm_atomic_helper_update_legacy_modeset_state+0x1d6/0x210 [drm_kms_helper]
 [   43.916623]  drm_atomic_helper_commit_planes+0xec/0x230 [drm_kms_helper]
 [   43.916995]  drm_atomic_helper_commit_tail+0x2b/0x60 [drm_kms_helper]
 [   43.917398]  commit_tail+0x65/0x70 [drm_kms_helper]
 [   43.917693]  drm_atomic_helper_commit+0xa9/0x100 [drm_kms_helper]
 [   43.918039]  drm_atomic_commit+0x4b/0x50 [drm]
 [   43.918334]  drm_atomic_helper_update_plane+0xf1/0x110 [drm_kms_helper]
 [   43.918902]  __setplane_internal+0x19f/0x280 [drm]
 [   43.919240]  drm_mode_cursor_universal+0x101/0x1c0 [drm]
 [   43.919541]  drm_mode_cursor_common+0x15b/0x1d0 [drm]
 [   43.919858]  drm_mode_cursor2_ioctl+0xe/0x10 [drm]
 [   43.920157]  drm_ioctl+0x211/0x460 [drm]
 [   43.920383]  ? drm_mode_cursor_ioctl+0x50/0x50 [drm]
 [   43.920664]  ? handle_mm_fault+0x93/0x160
 [   43.920893]  do_vfs_ioctl+0x96/0x6e0
 [   43.921117]  ? __fget+0x73/0xa0
 [   43.921322]  SyS_ioctl+0x41/0x70
 [   43.921545]  entry_SYSCALL_64_fastpath+0x1a/0xa5
 [   43.922188] RIP: 0033:0x7f1145804bc7
 [   43.922526] RSP: 002b:00007ffcd3e50508 EFLAGS: 00003246 ORIG_RAX: 0000000000000010
 [   43.923367] RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 00007f1145804bc7
 [   43.923852] RDX: 00007ffcd3e50540 RSI: 00000000c02464bb RDI: 000000000000000b
 [   43.924299] RBP: 0000000000000040 R08: 0000000000000040 R09: 000000000000000c
 [   43.924694] R10: 00007ffcd3e50340 R11: 0000000000003246 R12: 0000000000000018
 [   43.925128] R13: 00000000022bc390 R14: 0000000000000040 R15: 00007ffcd3e5062c

Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170519175819.15682-1-krisman@collabora.co.uk
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
drivers/gpu/drm/qxl/qxl_display.c