bisecting cause commit starting from b3a3cbdec55b090d22a09f75efb7c7d34cb97f25 building syzkaller on 65a7a8540d29e72622fca06522587f7e66539fd3 testing commit b3a3cbdec55b090d22a09f75efb7c7d34cb97f25 with gcc (GCC) 8.1.0 kernel signature: 73a62d84c0740102185e0e590338d08c898ca74031bfaf0536db94adea4c3949 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in hide_cursor testing release v5.10 testing commit 2c85ebc57b3e1817b6ce1a6b703928e113a90442 with gcc (GCC) 8.1.0 kernel signature: 395a614079c9030036488f72c030c4708fae86b9aba956ca15d15003efd3a593 all runs: OK # git bisect start b3a3cbdec55b090d22a09f75efb7c7d34cb97f25 2c85ebc57b3e1817b6ce1a6b703928e113a90442 Bisecting: 8942 revisions left to test after this (roughly 13 steps) [69f637c33560b02ae7313e0c142d847361cc723a] Merge tag 'for-5.11/drivers-2020-12-14' of git://git.kernel.dk/linux-block testing commit 69f637c33560b02ae7313e0c142d847361cc723a with gcc (GCC) 8.1.0 kernel signature: 8292d3254e702e2fb67646894f6213180f3866a30c88f7798d9ac65f76f643dc all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in hide_cursor # git bisect bad 69f637c33560b02ae7313e0c142d847361cc723a Bisecting: 3426 revisions left to test after this (roughly 12 steps) [d635a69dd4981cc51f90293f5f64268620ed1565] Merge tag 'net-next-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next testing commit d635a69dd4981cc51f90293f5f64268620ed1565 with gcc (GCC) 8.1.0 kernel signature: 02b0a0c06a62bc0c5f6949569bc2fb701980416436b80935124193928c5b1d69 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in hide_cursor # git bisect bad d635a69dd4981cc51f90293f5f64268620ed1565 Bisecting: 2735 revisions left to test after this (roughly 12 steps) [0ca2ce81eb8ee30f3ba8ac7967fef9cfbb44dbdb] Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux testing commit 0ca2ce81eb8ee30f3ba8ac7967fef9cfbb44dbdb with gcc (GCC) 8.1.0 kernel signature: 6fe2bb10814cded91adfd93541ddf8290d6ba010e5d6d6c249b1cb4deac5f7f2 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in hide_cursor # git bisect bad 0ca2ce81eb8ee30f3ba8ac7967fef9cfbb44dbdb Bisecting: 1417 revisions left to test after this (roughly 11 steps) [f8aab60422c371425365d386dfd51e0c6c5b1041] drm/amdgpu: Initialise drm_gem_object_funcs for imported BOs testing commit f8aab60422c371425365d386dfd51e0c6c5b1041 with gcc (GCC) 8.1.0 kernel signature: f902cb64dc32d009a6340c67f0349393056ef00cae3b1980e58107fc3c7ea1f2 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in hide_cursor # git bisect bad f8aab60422c371425365d386dfd51e0c6c5b1041 Bisecting: 882 revisions left to test after this (roughly 9 steps) [c0f98d2f8b076bf3e3183aa547395f919c943a14] Merge tag 'drm-misc-next-2020-11-05' of git://anongit.freedesktop.org/drm/drm-misc into drm-next testing commit c0f98d2f8b076bf3e3183aa547395f919c943a14 with gcc (GCC) 8.1.0 kernel signature: 0c3b148f3e25691198c50f38290096c95ab1d92bd398ca64b2459e2a862fa30f all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in hide_cursor # git bisect bad c0f98d2f8b076bf3e3183aa547395f919c943a14 Bisecting: 223 revisions left to test after this (roughly 8 steps) [6a6e5988a2657cd0c91f6f1a3e7d194599248b6d] drm/ttm: replace last move_notify with delete_mem_notify testing commit 6a6e5988a2657cd0c91f6f1a3e7d194599248b6d with gcc (GCC) 8.1.0 kernel signature: 3d7d852051c7c61b69639f140c269d31b1c443bdde732087cb14adc781e5f638 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in hide_cursor # git bisect bad 6a6e5988a2657cd0c91f6f1a3e7d194599248b6d Bisecting: 111 revisions left to test after this (roughly 7 steps) [291e8cdd6bc57658035239315d27f3f971ec062b] MAINTAINERS: mark FRAMEBUFFER LAYER as Orphan testing commit 291e8cdd6bc57658035239315d27f3f971ec062b with gcc (GCC) 8.1.0 kernel signature: aadd1cdae472cb0fe5af39d6e71243dd382e4d3b3e69bc8f460b2be3c8d382ef all runs: OK # git bisect good 291e8cdd6bc57658035239315d27f3f971ec062b Bisecting: 55 revisions left to test after this (roughly 6 steps) [787099f8671c5cec6cadbb3da3713d97df5c7fd6] drm/panel: mantix: Fix panel reset testing commit 787099f8671c5cec6cadbb3da3713d97df5c7fd6 with gcc (GCC) 8.1.0 kernel signature: e2dbeea0a8701b02c56ee922cbe6b50a3cbefa12d9813c28b2ac7d6bd57854be all runs: OK # git bisect good 787099f8671c5cec6cadbb3da3713d97df5c7fd6 Bisecting: 27 revisions left to test after this (roughly 5 steps) [7a1f4fa4a62933797152578d3730058fe6861b42] drm/panel: simple: Add YTC700TLAG-05-201C testing commit 7a1f4fa4a62933797152578d3730058fe6861b42 with gcc (GCC) 8.1.0 kernel signature: 8c8a56fac56b9a6bc38a247a4826ca0349177833d6396f5188eacc2184e80db5 all runs: OK # git bisect good 7a1f4fa4a62933797152578d3730058fe6861b42 Bisecting: 13 revisions left to test after this (roughly 4 steps) [c37d951cb42aa340513c0bc2df10b7324fa0d856] drm/ttm: add move old to system to drivers. testing commit c37d951cb42aa340513c0bc2df10b7324fa0d856 with gcc (GCC) 8.1.0 kernel signature: b56f1c336d1249ae8bdf0fb375784bd7c4bb7d98727b50ec5201544484acfefd all runs: OK # git bisect good c37d951cb42aa340513c0bc2df10b7324fa0d856 Bisecting: 6 revisions left to test after this (roughly 3 steps) [29a1d482e4044ab76d0c0f6341212f1a51f48236] drm/ttm: add move to system into drivers testing commit 29a1d482e4044ab76d0c0f6341212f1a51f48236 with gcc (GCC) 8.1.0 kernel signature: 7cdfae45b83a77bd21cbc965bc2d870d8bf30b8460b3f004d0fb38bbb29ed683 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in hide_cursor # git bisect bad 29a1d482e4044ab76d0c0f6341212f1a51f48236 Bisecting: 3 revisions left to test after this (roughly 2 steps) [1c831ade9f352d4690e2c3c67b674bc65cb3af3e] drm/komeda: Drop local dma_parms testing commit 1c831ade9f352d4690e2c3c67b674bc65cb3af3e with gcc (GCC) 8.1.0 kernel signature: 6fa311b5a690dac90ca92360cfb88c2ff5dc9489008dcbffce99399d50f594fb all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in hide_cursor # git bisect bad 1c831ade9f352d4690e2c3c67b674bc65cb3af3e Bisecting: 0 revisions left to test after this (roughly 1 step) [ea40d7857d5250e5400f38c69ef9e17321e9c4a2] drm/vkms: fbdev emulation support testing commit ea40d7857d5250e5400f38c69ef9e17321e9c4a2 with gcc (GCC) 8.1.0 kernel signature: 6fa311b5a690dac90ca92360cfb88c2ff5dc9489008dcbffce99399d50f594fb all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in hide_cursor # git bisect bad ea40d7857d5250e5400f38c69ef9e17321e9c4a2 Bisecting: 0 revisions left to test after this (roughly 0 steps) [23fae9cf97cc0ba54e4d6c8e078871f56370f271] drm/ttm: drop ttm_bo_move_ttm wrapper testing commit 23fae9cf97cc0ba54e4d6c8e078871f56370f271 with gcc (GCC) 8.1.0 kernel signature: bb925dfe66726ddb5d6ebbc9606d0642ed03e7494a2e0fb1ef12bf763e77cdfc all runs: OK # git bisect good 23fae9cf97cc0ba54e4d6c8e078871f56370f271 ea40d7857d5250e5400f38c69ef9e17321e9c4a2 is the first bad commit commit ea40d7857d5250e5400f38c69ef9e17321e9c4a2 Author: Daniel Vetter Date: Sat Oct 10 01:21:56 2020 +0200 drm/vkms: fbdev emulation support Hooray for generic fbdev support, making this a oneliner. We just needed to fix preferred_depth fixed and the vmap support added first. This is useful for testing fbdev testcases in igt. Right now we only have a simple one in the fbdev testcases, which passes both info and mmap subtests. v2: Augment commit message as suggested by Melissa. Acked-by: Thomas Zimmermann Reviewed-by: Melissa Wen Signed-off-by: Daniel Vetter Cc: Rodrigo Siqueira Cc: Melissa Wen Cc: Haneen Mohammed Cc: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20201009232156.3916879-3-daniel.vetter@ffwll.ch drivers/gpu/drm/vkms/vkms_drv.c | 2 ++ 1 file changed, 2 insertions(+) culprit signature: 6fa311b5a690dac90ca92360cfb88c2ff5dc9489008dcbffce99399d50f594fb parent signature: bb925dfe66726ddb5d6ebbc9606d0642ed03e7494a2e0fb1ef12bf763e77cdfc revisions tested: 16, total time: 2h35m3.039183565s (build: 1h13m45.063130717s, test: 1h19m48.275144082s) first bad commit: ea40d7857d5250e5400f38c69ef9e17321e9c4a2 drm/vkms: fbdev emulation support recipients (to): ["daniel.vetter@ffwll.ch" "daniel.vetter@intel.com" "melissa.srw@gmail.com" "tzimmermann@suse.de"] recipients (cc): [] crash: BUG: unable to handle kernel NULL pointer dereference in hide_cursor BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 11dbf4067 P4D 11dbf4067 PUD 11dbf5067 PMD 0 Oops: 0010 [#1] PREEMPT SMP CPU: 1 PID: 10184 Comm: syz-executor.2 Not tainted 5.9.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffffc90002463bb0 EFLAGS: 00010292 RAX: 0000000000000000 RBX: ffff88813b860800 RCX: 0000000000000000 RDX: 0000000000000002 RSI: ffff88813a3f3800 RDI: ffff88813b860800 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88811dbc9e00 R13: ffff88823aec92c0 R14: 0000000000000900 R15: 00000000000000a0 FS: 00007fe1bb259700(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000011dbf3000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: hide_cursor+0x1f/0x80 drivers/tty/vt/vt.c:906 redraw_screen+0x20e/0x2a0 drivers/tty/vt/vt.c:1011 vc_do_resize+0x52f/0x5a0 drivers/tty/vt/vt.c:1326 fbcon_set_disp+0x23c/0x370 drivers/video/fbdev/core/fbcon.c:1478 con2fb_init_display drivers/video/fbdev/core/fbcon.c:844 [inline] set_con2fb_map+0x30a/0xc40 drivers/video/fbdev/core/fbcon.c:915 fbcon_set_con2fb_map_ioctl+0xc0/0x1f0 drivers/video/fbdev/core/fbcon.c:3389 do_fb_ioctl+0x3d3/0x420 drivers/video/fbdev/core/fbmem.c:1156 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x7c/0xb0 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e219 Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fe1bb258c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045e219 RDX: 0000000020000080 RSI: 0000000000004610 RDI: 0000000000000004 RBP: 000000000119bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffc56c37f1f R14: 00007fe1bb2599c0 R15: 000000000119bf8c Modules linked in: CR2: 0000000000000000 ---[ end trace 1bf663bf4ff56a24 ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffffc90002463bb0 EFLAGS: 00010292 RAX: 0000000000000000 RBX: ffff88813b860800 RCX: 0000000000000000 RDX: 0000000000000002 RSI: ffff88813a3f3800 RDI: ffff88813b860800 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88811dbc9e00 R13: ffff88823aec92c0 R14: 0000000000000900 R15: 00000000000000a0 FS: 00007fe1bb259700(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000011dbf3000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400