| Message ID | 20250409170015.2651829-1-song@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] netfs: Only create /proc/fs/netfs with CONFIG_PROC_FS | expand |
Song Liu <song@kernel.org> wrote: > When testing a special config: > > CONFIG_NETFS_SUPPORTS=y > CONFIG_PROC_FS=n > > The system crashes with something like: > > [ 3.766197] ------------[ cut here ]------------ > [ 3.766484] kernel BUG at mm/mempool.c:560! > [ 3.766789] Oops: invalid opcode: 0000 [#1] SMP NOPTI > [ 3.767123] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G W > [ 3.767777] Tainted: [W]=WARN > [ 3.767968] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), > [ 3.768523] RIP: 0010:mempool_alloc_slab.cold+0x17/0x19 > [ 3.768847] Code: 50 fe ff 58 5b 5d 41 5c 41 5d 41 5e 41 5f e9 93 95 13 00 > [ 3.769977] RSP: 0018:ffffc90000013998 EFLAGS: 00010286 > [ 3.770315] RAX: 000000000000002f RBX: ffff888100ba8640 RCX: 0000000000000000 > [ 3.770749] RDX: 0000000000000000 RSI: 0000000000000003 RDI: 00000000ffffffff > [ 3.771217] RBP: 0000000000092880 R08: 0000000000000000 R09: ffffc90000013828 > [ 3.771664] R10: 0000000000000001 R11: 00000000ffffffea R12: 0000000000092cc0 > [ 3.772117] R13: 0000000000000400 R14: ffff8881004b1620 R15: ffffea0004ef7e40 > [ 3.772554] FS: 0000000000000000(0000) GS:ffff8881b5f3c000(0000) knlGS:0000000000000000 > [ 3.773061] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 3.773443] CR2: ffffffff830901b4 CR3: 0000000004296001 CR4: 0000000000770ef0 > [ 3.773884] PKRU: 55555554 > [ 3.774058] Call Trace: > [ 3.774232] <TASK> > [ 3.774371] mempool_alloc_noprof+0x6a/0x190 > [ 3.774649] ? _printk+0x57/0x80 > [ 3.774862] netfs_alloc_request+0x85/0x2ce > [ 3.775147] netfs_readahead+0x28/0x170 > [ 3.775395] read_pages+0x6c/0x350 > [ 3.775623] ? srso_alias_return_thunk+0x5/0xfbef5 > [ 3.775928] page_cache_ra_unbounded+0x1bd/0x2a0 > [ 3.776247] filemap_get_pages+0x139/0x970 > [ 3.776510] ? srso_alias_return_thunk+0x5/0xfbef5 > [ 3.776820] filemap_read+0xf9/0x580 > [ 3.777054] ? srso_alias_return_thunk+0x5/0xfbef5 > [ 3.777368] ? srso_alias_return_thunk+0x5/0xfbef5 > [ 3.777674] ? find_held_lock+0x32/0x90 > [ 3.777929] ? netfs_start_io_read+0x19/0x70 > [ 3.778221] ? netfs_start_io_read+0x19/0x70 > [ 3.778489] ? srso_alias_return_thunk+0x5/0xfbef5 > [ 3.778800] ? lock_acquired+0x1e6/0x450 > [ 3.779054] ? srso_alias_return_thunk+0x5/0xfbef5 > [ 3.779379] netfs_buffered_read_iter+0x57/0x80 > [ 3.779670] __kernel_read+0x158/0x2c0 > [ 3.779927] bprm_execve+0x300/0x7a0 > [ 3.780185] kernel_execve+0x10c/0x140 > [ 3.780423] ? __pfx_kernel_init+0x10/0x10 > [ 3.780690] kernel_init+0xd5/0x150 > [ 3.780910] ret_from_fork+0x2d/0x50 > [ 3.781156] ? __pfx_kernel_init+0x10/0x10 > [ 3.781414] ret_from_fork_asm+0x1a/0x30 > [ 3.781677] </TASK> > [ 3.781823] Modules linked in: > [ 3.782065] ---[ end trace 0000000000000000 ]--- > > This is caused by the following error path in netfs_init(): > > if (!proc_mkdir("fs/netfs", NULL)) > goto error_proc; > > Fix this by adding ifdef in netfs_main(), so that /proc/fs/netfs is only > created with CONFIG_PROC_FS. > > Signed-off-by: Song Liu <song@kernel.org> Acked-by: David Howells <dhowells@redhat.com>
On Wed, 09 Apr 2025 10:00:15 -0700, Song Liu wrote: > When testing a special config: > > CONFIG_NETFS_SUPPORTS=y > CONFIG_PROC_FS=n > > The system crashes with something like: > > [...] Applied to the vfs.fixes branch of the vfs/vfs.git tree. Patches in the vfs.fixes branch should appear in linux-next soon. Please report any outstanding bugs that were missed during review in a new review to the original patch series allowing us to drop it. It's encouraged to provide Acked-bys and Reviewed-bys even though the patch has now been applied. If possible patch trailers will be updated. Note that commit hashes shown below are subject to change due to rebase, trailer updates or similar. If in doubt, please check the listed branch. tree: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git branch: vfs.fixes [1/1] netfs: Only create /proc/fs/netfs with CONFIG_PROC_FS https://git.kernel.org/vfs/vfs/c/40cb48eba3b4
diff --git a/fs/netfs/main.c b/fs/netfs/main.c index 4e3e62040831..70ecc8f5f210 100644 --- a/fs/netfs/main.c +++ b/fs/netfs/main.c @@ -127,11 +127,13 @@ static int __init netfs_init(void) if (mempool_init_slab_pool(&netfs_subrequest_pool, 100, netfs_subrequest_slab) < 0) goto error_subreqpool; +#ifdef CONFIG_PROC_FS if (!proc_mkdir("fs/netfs", NULL)) goto error_proc; if (!proc_create_seq("fs/netfs/requests", S_IFREG | 0444, NULL, &netfs_requests_seq_ops)) goto error_procfile; +#endif #ifdef CONFIG_FSCACHE_STATS if (!proc_create_single("fs/netfs/stats", S_IFREG | 0444, NULL, netfs_stats_show)) @@ -144,9 +146,11 @@ static int __init netfs_init(void) return 0; error_fscache: +#ifdef CONFIG_PROC_FS error_procfile: remove_proc_subtree("fs/netfs", NULL); error_proc: +#endif mempool_exit(&netfs_subrequest_pool); error_subreqpool: kmem_cache_destroy(netfs_subrequest_slab);
When testing a special config: CONFIG_NETFS_SUPPORTS=y CONFIG_PROC_FS=n The system crashes with something like: [ 3.766197] ------------[ cut here ]------------ [ 3.766484] kernel BUG at mm/mempool.c:560! [ 3.766789] Oops: invalid opcode: 0000 [#1] SMP NOPTI [ 3.767123] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G W [ 3.767777] Tainted: [W]=WARN [ 3.767968] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), [ 3.768523] RIP: 0010:mempool_alloc_slab.cold+0x17/0x19 [ 3.768847] Code: 50 fe ff 58 5b 5d 41 5c 41 5d 41 5e 41 5f e9 93 95 13 00 [ 3.769977] RSP: 0018:ffffc90000013998 EFLAGS: 00010286 [ 3.770315] RAX: 000000000000002f RBX: ffff888100ba8640 RCX: 0000000000000000 [ 3.770749] RDX: 0000000000000000 RSI: 0000000000000003 RDI: 00000000ffffffff [ 3.771217] RBP: 0000000000092880 R08: 0000000000000000 R09: ffffc90000013828 [ 3.771664] R10: 0000000000000001 R11: 00000000ffffffea R12: 0000000000092cc0 [ 3.772117] R13: 0000000000000400 R14: ffff8881004b1620 R15: ffffea0004ef7e40 [ 3.772554] FS: 0000000000000000(0000) GS:ffff8881b5f3c000(0000) knlGS:0000000000000000 [ 3.773061] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3.773443] CR2: ffffffff830901b4 CR3: 0000000004296001 CR4: 0000000000770ef0 [ 3.773884] PKRU: 55555554 [ 3.774058] Call Trace: [ 3.774232] <TASK> [ 3.774371] mempool_alloc_noprof+0x6a/0x190 [ 3.774649] ? _printk+0x57/0x80 [ 3.774862] netfs_alloc_request+0x85/0x2ce [ 3.775147] netfs_readahead+0x28/0x170 [ 3.775395] read_pages+0x6c/0x350 [ 3.775623] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.775928] page_cache_ra_unbounded+0x1bd/0x2a0 [ 3.776247] filemap_get_pages+0x139/0x970 [ 3.776510] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.776820] filemap_read+0xf9/0x580 [ 3.777054] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.777368] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.777674] ? find_held_lock+0x32/0x90 [ 3.777929] ? netfs_start_io_read+0x19/0x70 [ 3.778221] ? netfs_start_io_read+0x19/0x70 [ 3.778489] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.778800] ? lock_acquired+0x1e6/0x450 [ 3.779054] ? srso_alias_return_thunk+0x5/0xfbef5 [ 3.779379] netfs_buffered_read_iter+0x57/0x80 [ 3.779670] __kernel_read+0x158/0x2c0 [ 3.779927] bprm_execve+0x300/0x7a0 [ 3.780185] kernel_execve+0x10c/0x140 [ 3.780423] ? __pfx_kernel_init+0x10/0x10 [ 3.780690] kernel_init+0xd5/0x150 [ 3.780910] ret_from_fork+0x2d/0x50 [ 3.781156] ? __pfx_kernel_init+0x10/0x10 [ 3.781414] ret_from_fork_asm+0x1a/0x30 [ 3.781677] </TASK> [ 3.781823] Modules linked in: [ 3.782065] ---[ end trace 0000000000000000 ]--- This is caused by the following error path in netfs_init(): if (!proc_mkdir("fs/netfs", NULL)) goto error_proc; Fix this by adding ifdef in netfs_main(), so that /proc/fs/netfs is only created with CONFIG_PROC_FS. Signed-off-by: Song Liu <song@kernel.org> --- fs/netfs/main.c | 4 ++++ 1 file changed, 4 insertions(+)