Hello, syzbot found the following issue on: HEAD commit: 2ccdd1b13c59 Linux 6.5-rc6 git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=143b6d3ba80000 kernel config: https://syzkaller.appspot.com/x/.config?x=8fc59e2140295873 dashboard link: https://syzkaller.appspot.com/bug?extid=cfba1abcb2cf7b39a320 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1032446ba80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16576b4fa80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/e6e598627dd6/disk-2ccdd1b1.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/486c6739d779/vmlinux-2ccdd1b1.xz kernel image: https://storage.googleapis.com/syzbot-assets/5da0f3ac1d56/bzImage-2ccdd1b1.xz The issue was bisected to: commit a5b44c4adb1699661d22e5152fb26885f30a2e4c Author: Thomas Zimmermann <tzimmermann@xxxxxxx> Date: Mon Mar 20 15:07:44 2023 +0000 drm/fbdev-generic: Always use shadow buffering bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=11349b73a80000 final oops: https://syzkaller.appspot.com/x/report.txt?x=13349b73a80000 console output: https://syzkaller.appspot.com/x/log.txt?x=15349b73a80000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+cfba1abcb2cf7b39a320@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: a5b44c4adb16 ("drm/fbdev-generic: Always use shadow buffering") vm_area_alloc_pages mm/vmalloc.c:3059 [inline] __vmalloc_area_node mm/vmalloc.c:3135 [inline] __vmalloc_node_range+0xa6e/0x1540 mm/vmalloc.c:3316 __vmalloc_node mm/vmalloc.c:3381 [inline] vzalloc+0x6b/0x80 mm/vmalloc.c:3454 drm_fbdev_generic_helper_fb_probe+0x300/0x6d0 drivers/gpu/drm/drm_fbdev_generic.c:97 drm_fb_helper_single_fb_probe drivers/gpu/drm/drm_fb_helper.c:1668 [inline] __drm_fb_helper_initial_config_and_unlock+0xc31/0x1600 drivers/gpu/drm/drm_fb_helper.c:1846 drm_fb_helper_initial_config drivers/gpu/drm/drm_fb_helper.c:1936 [inline] drm_fb_helper_initial_config+0x44/0x60 drivers/gpu/drm/drm_fb_helper.c:1928 drm_fbdev_generic_client_hotplug+0x1a7/0x270 drivers/gpu/drm/drm_fbdev_generic.c:280 drm_client_register+0x195/0x280 drivers/gpu/drm/drm_client.c:149 drm_fbdev_generic_setup+0x11c/0x330 drivers/gpu/drm/drm_fbdev_generic.c:342 vkms_create drivers/gpu/drm/vkms/vkms_drv.c:208 [inline] vkms_init+0x625/0x760 drivers/gpu/drm/vkms/vkms_drv.c:234 do_one_initcall+0x117/0x630 init/main.c:1232 do_initcall_level init/main.c:1294 [inline] do_initcalls init/main.c:1310 [inline] do_basic_setup init/main.c:1329 [inline] kernel_init_freeable+0x5bd/0x8f0 init/main.c:1546 page_owner free stack trace missing ------------[ cut here ]------------ kernel BUG at mm/memory.c:2955! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 5026 Comm: syz-executor380 Not tainted 6.5.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 RIP: 0010:do_page_mkwrite+0x468/0x680 mm/memory.c:2955 Code: de e8 cc 15 c2 ff 84 db 0f 85 c1 00 00 00 48 89 eb e9 76 fe ff ff e8 87 1a c2 ff 48 c7 c6 a0 b3 78 8a 48 89 ef e8 78 3d fe ff <0f> 0b 41 bc 02 00 00 00 e9 99 fe ff ff e8 66 1a c2 ff be d0 03 00 RSP: 0018:ffffc900030efba8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888079cec200 RSI: ffffffff81c30648 RDI: ffffffff8ac7eec0 RBP: ffffea0005007780 R08: 0000000000000000 R09: fffffbfff1d55d7a R10: ffffffff8eaaebd7 R11: 0000000000000001 R12: 0000000000000200 R13: ffffea0005007780 R14: 0000000000000a55 R15: 0000000000000000 FS: 0000555557128380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb85a07fe08 CR3: 0000000023b67000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> wp_page_shared mm/memory.c:3294 [inline] do_wp_page+0x3a0/0x3710 mm/memory.c:3376 handle_pte_fault mm/memory.c:4955 [inline] __handle_mm_fault+0x1af7/0x3b80 mm/memory.c:5079 handle_mm_fault+0x2ab/0x9d0 mm/memory.c:5233 do_user_addr_fault+0x446/0xfc0 arch/x86/mm/fault.c:1392 handle_page_fault arch/x86/mm/fault.c:1486 [inline] exc_page_fault+0x5c/0xd0 arch/x86/mm/fault.c:1542 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0033:0x7fb859ff27a0 Code: 00 41 b8 11 80 02 00 b9 06 00 00 01 ba 00 60 b3 00 be 00 00 00 20 bf 09 00 00 00 31 c0 48 c7 04 24 00 c0 2f 00 e8 30 fc 02 00 <c6> 04 25 08 00 00 20 00 45 31 c0 48 b8 2f 64 65 76 2f 66 62 30 b9 RSP: 002b:00007ffeec409b10 EFLAGS: 00010217 RAX: 0000000020000000 RBX: 00007ffeec409ce8 RCX: 00007fb85a0223e9 RDX: 0000000001000006 RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007fb85a095610 R08: 0000000000000004 R09: 00000000002fc000 R10: 0000000000028011 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffeec409cd8 R14: 0000000000000001 R15: 0000000000000001 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:do_page_mkwrite+0x468/0x680 mm/memory.c:2955 Code: de e8 cc 15 c2 ff 84 db 0f 85 c1 00 00 00 48 89 eb e9 76 fe ff ff e8 87 1a c2 ff 48 c7 c6 a0 b3 78 8a 48 89 ef e8 78 3d fe ff <0f> 0b 41 bc 02 00 00 00 e9 99 fe ff ff e8 66 1a c2 ff be d0 03 00 RSP: 0018:ffffc900030efba8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888079cec200 RSI: ffffffff81c30648 RDI: ffffffff8ac7eec0 RBP: ffffea0005007780 R08: 0000000000000000 R09: fffffbfff1d55d7a R10: ffffffff8eaaebd7 R11: 0000000000000001 R12: 0000000000000200 R13: ffffea0005007780 R14: 0000000000000a55 R15: 0000000000000000 FS: 0000555557128380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb85a07fe08 CR3: 0000000023b67000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
