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WARNING in __kvm_gpc_refresh (3)

Status: upstream: reported C repro on 2025/01/02 09:06
Subsystems: kvm
[Documentation on labels]
Reported-by: syzbot+cde12433b6c56f55d9ed@syzkaller.appspotmail.com
First crash: 476d, last: 4d09h
Cause bisection: failed (error log, bisect log)
  
▶ ▼ Discussions (11)
Title Replies (including bot) Last reply
[syzbot] Monthly kvm report (Mar 2026) 0 (1) 2026/03/27 20:35
[PATCH] KVM: pfncache: Fix uhva validity check in kvm_gpc_is_valid_len() 4 (4) 2026/03/09 19:39
[syzbot] [kvm?] WARNING in __kvm_gpc_refresh (3) 0 (4) 2026/03/09 05:15
[syzbot] Monthly kvm report (Feb 2026) 0 (1) 2026/02/16 12:34
[syzbot] Monthly kvm report (Jan 2026) 0 (1) 2026/01/12 08:40
[syzbot] Monthly kvm report (Dec 2025) 0 (1) 2025/12/11 05:58
[syzbot] Monthly kvm report (Nov 2025) 0 (1) 2025/11/10 09:15
[syzbot] Monthly kvm report (Oct 2025) 0 (1) 2025/10/10 07:32
[syzbot] Monthly kvm report (Sep 2025) 0 (1) 2025/09/01 07:38
[syzbot] Monthly kvm report (May 2025) 0 (1) 2025/05/12 13:34
[syzbot] Monthly kvm report (Jan 2025) 0 (1) 2025/01/13 10:54
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in __kvm_gpc_refresh kvm -1 C 178 698d 762d 25/29 fixed on 2024/05/22 23:08
upstream WARNING in __kvm_gpc_refresh (2) kvm -1 C error 2 677d 691d 27/29 fixed on 2024/08/14 03:44
▶ ▼ Last patch testing requests (12)
Created Duration User Patch Repo Result
2026/03/29 23:35 19m retest repro linux-next report log
2026/03/09 05:15 17m phind.uet@gmail.com patch linux-next OK log
2026/03/09 04:25 12m phind.uet@gmail.com linux-next report log
2026/02/27 10:22 13m retest repro upstream report log
2026/02/04 23:09 56m retest repro linux-next report log
2026/02/04 23:09 58m retest repro linux-next report log
2026/02/04 23:26 13m retest repro upstream report log
2026/02/04 23:04 16m retest repro upstream log
2025/10/16 08:13 19m retest repro linux-next report log
2025/10/16 08:13 20m retest repro linux-next report log
2025/10/02 04:33 14m retest repro upstream report log
2025/08/02 09:16 8m retest repro linux-next error

Sample crash report:
kvm_intel: L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.
------------[ cut here ]------------
kvm_is_error_gpa(gpa) == kvm_is_error_hva(uhva)
WARNING: arch/x86/kvm/../../../virt/kvm/pfncache.c:267 at __kvm_gpc_refresh+0x1219/0x13a0 virt/kvm/pfncache.c:267, CPU#0: syz.0.17/6008
Modules linked in:
CPU: 0 UID: 0 PID: 6008 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:__kvm_gpc_refresh+0x1219/0x13a0 virt/kvm/pfncache.c:267
Code: c6 05 72 ab ba 0e 01 48 c7 c7 18 36 ee 8d be 34 04 00 00 48 c7 c2 00 3d c2 8b e8 62 e0 60 00 e9 6a f1 ff ff e8 18 bf 84 00 90 <0f> 0b 90 bb ea ff ff ff e9 a4 f8 ff ff e8 05 bf 84 00 90 0f 0b 90
RSP: 0018:ffffc90002f271c0 EFLAGS: 00010293
RAX: ffffffff814100d8 RBX: ffff888000000000 RCX: ffff888035479e80
RDX: 0000000000000000 RSI: ffff888000000000 RDI: ffff888000000000
RBP: ffffc90002f27348 R08: ffffffff9011dab7 R09: 1ffffffff2023b56
R10: dffffc0000000000 R11: fffffbfff2023b57 R12: ffff888078391290
R13: dffffc0000000000 R14: ffff888000000000 R15: ffffffffffffff01
FS:  000055556a986500(0000) GS:ffff888125454000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000000 CR3: 0000000036cb6000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 kvm_gpc_refresh+0xe1/0x140 virt/kvm/pfncache.c:382
 kvm_xen_set_evtchn+0x163/0x230 arch/x86/kvm/xen.c:1942
 kvm_xen_hvm_evtchn_send+0x120/0x1e0 arch/x86/kvm/xen.c:2033
 kvm_arch_vm_ioctl+0xfb1/0x1a10 arch/x86/kvm/x86.c:7518
 kvm_vm_ioctl+0x905/0xd50 virt/kvm/kvm_main.c:5387
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f92ca59c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff43137188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f92ca815fa0 RCX: 00007f92ca59c819
RDX: 0000200000000400 RSI: 00000000400caed0 RDI: 0000000000000005
RBP: 00007f92ca632c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f92ca815fac R14: 00007f92ca815fa0 R15: 00007f92ca815fa0
 </TASK>

Crashes (87):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/10 11:59 upstream 9a9c8ce300cd 38c8e246 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in __kvm_gpc_refresh
2026/02/05 04:15 upstream f14faaf3a1fb ea10c935 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2025/10/26 23:54 upstream dbfc6422a34d c0460fcd .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __kvm_gpc_refresh
2025/06/25 15:49 upstream 7595b66ae9de 26d77996 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/02/13 09:41 linux-next af98e93c5c39 6a673c50 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in __kvm_gpc_refresh
2026/02/05 04:52 linux-next 0f8a890c4524 ea10c935 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __kvm_gpc_refresh
2025/10/27 03:31 linux-next 72fb0170ef1f c0460fcd .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __kvm_gpc_refresh
2025/06/26 17:13 linux-next ecb259c4f70d 26d77996 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __kvm_gpc_refresh
2025/02/26 17:35 linux-next e5d3fd687aac d34966d1 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in __kvm_gpc_refresh
2026/04/07 09:05 upstream bfe62a454542 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in __kvm_gpc_refresh
2026/04/06 01:22 upstream 1791c390149f 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in __kvm_gpc_refresh
2026/03/31 19:33 upstream d0c3bcd5b897 aeea1c72 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in __kvm_gpc_refresh
2026/03/31 00:11 upstream 7aaa8047eafd 458630d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in __kvm_gpc_refresh
2026/01/08 13:37 upstream f0b9d8eb98df d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in __kvm_gpc_refresh
2026/01/04 13:53 upstream aacb0a6d604a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in __kvm_gpc_refresh
2025/12/06 12:21 upstream 51d90a15fedf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in __kvm_gpc_refresh
2025/11/09 12:20 upstream 7bb4d6512545 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in __kvm_gpc_refresh
2025/11/08 11:18 upstream 38a2c275c3d3 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __kvm_gpc_refresh
2025/12/26 12:02 upstream ccd1cdca5cd4 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in __kvm_gpc_refresh
2026/04/15 22:26 upstream 1f5ffc672165 2b1eb0ca .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/04/15 16:01 upstream 1f5ffc672165 2b1eb0ca .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/04/13 12:13 upstream 028ef9c96e96 9530ccf9 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/04/10 04:32 upstream a55f7f5f29b3 38c8e246 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/04/08 08:47 upstream 3036cd0d3328 2c961e87 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/04/07 17:06 upstream bfe62a454542 628666c6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __kvm_gpc_refresh
2026/04/05 13:55 upstream 3aae9383f42f 4440e7c2 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/04/04 18:25 upstream 7ca6d1cfec80 4440e7c2 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/04/02 23:25 upstream 5619b098e2fb 4440e7c2 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/03/15 21:32 upstream 4f3df2e5ea69 ee8d34d6 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/03/14 01:38 upstream b36eb6e3f5d8 351cb5cf .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/03/11 12:10 upstream b4f0dd314b39 86914af9 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/03/07 02:32 upstream 651690480a96 5cb44a80 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __kvm_gpc_refresh
2026/03/06 21:55 upstream 651690480a96 41d8037d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/03/03 19:31 upstream af4e9ef3d784 4180d919 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/03/02 11:01 upstream 11439c4635ed 43249bac .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/02/07 14:50 upstream 2687c848e578 f20fc9f9 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/02/05 03:50 upstream f14faaf3a1fb ea10c935 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/01/21 23:01 upstream cf38b2340c0e d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/01/04 22:05 upstream 54e82e93ca93 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __kvm_gpc_refresh
2025/12/31 06:05 upstream dbf8fe85a16a d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2025/12/27 02:41 upstream 3f0e9c8cefa9 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2025/12/26 07:31 upstream ccd1cdca5cd4 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2025/12/14 22:42 upstream 8f0b4cce4481 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2025/11/24 00:39 upstream d0e88704d96c 4fb8ef37 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __kvm_gpc_refresh
2025/11/23 06:19 upstream 89edd36fd801 4fb8ef37 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __kvm_gpc_refresh
2025/11/20 05:57 upstream 23cb64fb7625 26ee5237 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __kvm_gpc_refresh
2025/11/19 04:01 upstream 5bebe8de1926 ef766cd7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __kvm_gpc_refresh
2025/11/13 05:51 upstream e927c520e1ba 07e030de .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __kvm_gpc_refresh
2025/11/10 02:11 upstream 439fc29dfd3b 4e1406b4 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __kvm_gpc_refresh
2025/11/07 13:37 upstream 4a0c9b339199 4e1406b4 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2025/11/06 13:15 upstream dc77806cf3b4 a6c9c731 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2024/12/29 08:58 upstream 059dd502b263 d3ccff63 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __kvm_gpc_refresh
2026/04/11 07:44 upstream 7c6c4ed80b87 38c8e246 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __kvm_gpc_refresh
2026/03/14 15:17 upstream 1c9982b49613 ee8d34d6 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __kvm_gpc_refresh
2026/01/21 21:37 upstream 6c790212c588 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __kvm_gpc_refresh
2026/01/02 14:56 upstream b69053dd3ffb d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __kvm_gpc_refresh
2026/04/12 02:20 linux-next cc13002a9f98 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __kvm_gpc_refresh
2026/04/06 19:41 linux-next cc13002a9f98 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __kvm_gpc_refresh
2026/03/13 10:43 linux-next 5c9e55fecf93 2f7f359d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __kvm_gpc_refresh
2026/01/20 02:11 linux-next d08c85ac8894 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __kvm_gpc_refresh
2025/11/11 19:08 linux-next 2666975a8905 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __kvm_gpc_refresh
2025/11/08 03:57 linux-next 9c0826a5d9aa 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __kvm_gpc_refresh
* Struck through repros no longer work on HEAD.