The commit ced17ee32a99 ("Revert "virtio: reject shm region if length is zero"")
exposes the following DAX page fault bug:
The commit 21aa65bf82a7 ("mm: remove callers of pfn_t functionality") handles
the DAX physical page address incorrectly: the removed macro 'phys_to_pfn_t()'
should be replaced with 'PHYS_PFN()'.
[ 1.390321] BUG: unable to handle page fault for address: ffffd3fb40000008
[ 1.390875] #PF: supervisor read access in kernel mode
[ 1.391257] #PF: error_code(0x0000) - not-present page
[ 1.391509] PGD 0 P4D 0
[ 1.391626] Oops: Oops: 0000 [#1] SMP NOPTI
[ 1.391806] CPU: 6 UID: 1000 PID: 162 Comm: weston Not tainted
6.17.0-rc3-WSL2-STABLE #2 PREEMPT(none)
[ 1.392361] RIP: 0010:dax_to_folio+0x14/0x60
[ 1.392653] Code: 52 c9 c3 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90
90 90 90 0f 1f 44 00 00 48 c1 ef 05 48 c1 e7 06 48 03 3d 34 b5 31 01 <48> 8b 57
08 48 89 f8 f6 c2 01 75 2b 66 90 c3 cc cc cc cc f7 c7 ff
[ 1.393727] RSP: 0000:ffffaf7d04407aa8 EFLAGS: 00010086
[ 1.394003] RAX: 000000a000000000 RBX: ffffaf7d04407bb0 RCX: 0000000000000000
[ 1.394524] RDX: ffffd17b40000008 RSI: 0000000000000083 RDI: ffffd3fb40000000
[ 1.394967] RBP: 0000000000000011 R08: 000000a000000000 R09: 0000000000000000
[ 1.395400] R10: 0000000000001000 R11: ffffaf7d04407c10 R12: 0000000000000000
[ 1.395806] R13: ffffa020557be9c0 R14: 0000014000000001 R15: 0000725970e94000
[ 1.396268] FS: 000072596d6d2ec0(0000) GS:ffffa0222dc59000(0000)
knlGS:0000000000000000
[ 1.396715] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1.397100] CR2: ffffd3fb40000008 CR3: 000000011579c005 CR4: 0000000000372ef0
[ 1.397518] Call Trace:
[ 1.397663] <TASK>
[ 1.397900] dax_insert_entry+0x13b/0x390
[ 1.398179] dax_fault_iter+0x2a5/0x6c0
[ 1.398443] dax_iomap_pte_fault+0x193/0x3c0
[ 1.398750] __fuse_dax_fault+0x8b/0x270
[ 1.398997] ? vm_mmap_pgoff+0x161/0x210
[ 1.399175] __do_fault+0x30/0x180
[ 1.399360] do_fault+0xc4/0x550
[ 1.399547] __handle_mm_fault+0x8e3/0xf50
[ 1.399731] ? do_syscall_64+0x72/0x1e0
[ 1.399958] handle_mm_fault+0x192/0x2f0
[ 1.400204] do_user_addr_fault+0x20e/0x700
[ 1.400418] exc_page_fault+0x66/0x150
[ 1.400602] asm_exc_page_fault+0x26/0x30
[ 1.400831] RIP: 0033:0x72596d1bf703
[ 1.401076] Code: 31 f6 45 31 e4 48 8d 15 b3 73 00 00 e8 06 03 00 00 8b 83
68 01 00 00 e9 8e fa ff ff 0f 1f 00 48 8b 44 24 08 4c 89 ee 48 89 df <c7> 00 21
43 34 12 e8 72 09 00 00 e9 6a fa ff ff 0f 1f 44 00 00 e8
[ 1.402172] RSP: 002b:00007ffc350f6dc0 EFLAGS: 00010202
[ 1.402488] RAX: 0000725970e94000 RBX: 00005b7c642c2560 RCX: 0000725970d359a7
[ 1.402898] RDX: 0000000000000003 RSI: 00007ffc350f6dc0 RDI: 00005b7c642c2560
[ 1.403284] RBP: 00007ffc350f6e90 R08: 000000000000000d R09: 0000000000000000
[ 1.403634] R10: 00007ffc350f6dd8 R11: 0000000000000246 R12: 0000000000000001
[ 1.404078] R13: 00007ffc350f6dc0 R14: 0000725970e29ce0 R15: 0000000000000003
[ 1.404450] </TASK>
[ 1.404570] Modules linked in:
[ 1.404821] CR2: ffffd3fb40000008
[ 1.405029] ---[ end trace 0000000000000000 ]---
[ 1.405323] RIP: 0010:dax_to_folio+0x14/0x60
[ 1.405556] Code: 52 c9 c3 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90
90 90 90 0f 1f 44 00 00 48 c1 ef 05 48 c1 e7 06 48 03 3d 34 b5 31 01 <48> 8b 57
08 48 89 f8 f6 c2 01 75 2b 66 90 c3 cc cc cc cc f7 c7 ff
[ 1.406639] RSP: 0000:ffffaf7d04407aa8 EFLAGS: 00010086
[ 1.406910] RAX: 000000a000000000 RBX: ffffaf7d04407bb0 RCX: 0000000000000000
[ 1.407379] RDX: ffffd17b40000008 RSI: 0000000000000083 RDI: ffffd3fb40000000
[ 1.407800] RBP: 0000000000000011 R08: 000000a000000000 R09: 0000000000000000
[ 1.408246] R10: 0000000000001000 R11: ffffaf7d04407c10 R12: 0000000000000000
[ 1.408666] R13: ffffa020557be9c0 R14: 0000014000000001 R15: 0000725970e94000
[ 1.409170] FS: 000072596d6d2ec0(0000) GS:ffffa0222dc59000(0000)
knlGS:0000000000000000
[ 1.409608] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1.409977] CR2: ffffd3fb40000008 CR3: 000000011579c005 CR4: 0000000000372ef0
[ 1.410437] Kernel panic - not syncing: Fatal exception
[ 1.410857] Kernel Offset: 0xc000000 from 0xffffffff81000000 (relocation
range: 0xffffffff80000000-0xffffffffbfffffff)
Fixes: 21aa65bf82a7 ("mm: remove callers of pfn_t functionality")
Signed-off-by: Haiyue Wang <haiyu...@163.com>
---
fs/fuse/virtio_fs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
index c826e7ca49f5..76c8fd0bfc75 100644
--- a/fs/fuse/virtio_fs.c
+++ b/fs/fuse/virtio_fs.c
@@ -1016,7 +1016,7 @@ static long virtio_fs_direct_access(struct dax_device
*dax_dev, pgoff_t pgoff,
if (kaddr)
*kaddr = fs->window_kaddr + offset;
if (pfn)
- *pfn = fs->window_phys_addr + offset;
+ *pfn = PHYS_PFN(fs->window_phys_addr + offset);
return nr_pages > max_nr_pages ? max_nr_pages : nr_pages;
}
--
2.51.0
