From 66314e9a57a050f95cb0ebac904f5ab047a8926e Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 2 Feb 2025 16:50:14 -0800 Subject: [PATCH 1/6] xfs: fix online repair probing when CONFIG_XFS_ONLINE_REPAIR=n I received a report from the release engineering side of the house that xfs_scrub without the -n flag (aka fix it mode) would try to fix a broken filesystem even on a kernel that doesn't have online repair built into it: # xfs_scrub -dTvn /mnt/test EXPERIMENTAL xfs_scrub program in use! Use at your own risk! Phase 1: Find filesystem geometry. /mnt/test: using 1 threads to scrub. Phase 1: Memory used: 132k/0k (108k/25k), time: 0.00/ 0.00/ 0.00s Phase 4: Repair filesystem. Info: /mnt/test/some/victimdir directory entries: Attempting repair. (repair.c line 351) Corruption: /mnt/test/some/victimdir directory entries: Repair unsuccessful; offline repair required. (repair.c line 204) Source: https://blogs.oracle.com/linux/post/xfs-online-filesystem-repair It is strange that xfs_scrub doesn't refuse to run, because the kernel is supposed to return EOPNOTSUPP if we actually needed to run a repair, and xfs_io's repair subcommand will perror that. And yet: # xfs_io -x -c 'repair probe' /mnt/test # The first problem is commit dcb660f9222fd9 (4.15) which should have had xchk_probe set the CORRUPT OFLAG so that any of the repair machinery will get called at all. It turns out that some refactoring that happened in the 6.6-6.8 era broke the operation of this corner case. What we *really* want to happen is that all the predicates that would steer xfs_scrub_metadata() towards calling xrep_attempt() should function the same way that they do when repair is compiled in; and then xrep_attempt gets to return the fatal EOPNOTSUPP error code that causes the probe to fail. Instead, commit 8336a64eb75cba (6.6) started the failwhale swimming by hoisting OFLAG checking logic into a helper whose non-repair stub always returns false, causing scrub to return "repair not needed" when in fact the repair is not supported. Prior to that commit, the oflag checking that was open-coded in scrub.c worked correctly. Similarly, in commit 4bdfd7d15747b1 (6.8) we hoisted the IFLAG_REPAIR and ALREADY_FIXED logic into a helper whose non-repair stub always returns false, so we never enter the if test body that would have called xrep_attempt, let alone fail to decode the OFLAGs correctly. The final insult (yes, we're doing The Naked Gun now) is commit 48a72f60861f79 (6.8) in which we hoisted the "are we going to try a repair?" predicate into yet another function with a non-repair stub always returns false. Fix xchk_probe to trigger xrep_probe if repair is enabled, or return EOPNOTSUPP directly if it is not. For all the other scrub types, we need to fix the header predicates so that the ->repair functions (which are all xrep_notsupported) get called to return EOPNOTSUPP. Commit 48a72 is tagged here because the scrub code prior to LTS 6.12 are incomplete and not worth patching. Reported-by: David Flynn Cc: # v6.8 Fixes: 8336a64eb75c ("xfs: don't complain about unfixed metadata when repairs were injected") Signed-off-by: "Darrick J. Wong" Reviewed-by: Christoph Hellwig Signed-off-by: Carlos Maiolino --- fs/xfs/scrub/common.h | 5 ----- fs/xfs/scrub/repair.h | 11 ++++++++++- fs/xfs/scrub/scrub.c | 12 ++++++++++++ 3 files changed, 22 insertions(+), 6 deletions(-) diff --git a/fs/xfs/scrub/common.h b/fs/xfs/scrub/common.h index bdcd40f0ec74..19877d99f255 100644 --- a/fs/xfs/scrub/common.h +++ b/fs/xfs/scrub/common.h @@ -224,7 +224,6 @@ static inline bool xchk_skip_xref(struct xfs_scrub_metadata *sm) bool xchk_dir_looks_zapped(struct xfs_inode *dp); bool xchk_pptr_looks_zapped(struct xfs_inode *ip); -#ifdef CONFIG_XFS_ONLINE_REPAIR /* Decide if a repair is required. */ static inline bool xchk_needs_repair(const struct xfs_scrub_metadata *sm) { @@ -244,10 +243,6 @@ static inline bool xchk_could_repair(const struct xfs_scrub *sc) return (sc->sm->sm_flags & XFS_SCRUB_IFLAG_REPAIR) && !(sc->flags & XREP_ALREADY_FIXED); } -#else -# define xchk_needs_repair(sc) (false) -# define xchk_could_repair(sc) (false) -#endif /* CONFIG_XFS_ONLINE_REPAIR */ int xchk_metadata_inode_forks(struct xfs_scrub *sc); diff --git a/fs/xfs/scrub/repair.h b/fs/xfs/scrub/repair.h index 823c00d1a502..af0a3a9e5ed9 100644 --- a/fs/xfs/scrub/repair.h +++ b/fs/xfs/scrub/repair.h @@ -191,7 +191,16 @@ int xrep_reset_metafile_resv(struct xfs_scrub *sc); #else #define xrep_ino_dqattach(sc) (0) -#define xrep_will_attempt(sc) (false) + +/* + * When online repair is not built into the kernel, we still want to attempt + * the repair so that the stub xrep_attempt below will return EOPNOTSUPP. + */ +static inline bool xrep_will_attempt(const struct xfs_scrub *sc) +{ + return (sc->sm->sm_flags & XFS_SCRUB_IFLAG_FORCE_REBUILD) || + xchk_needs_repair(sc->sm); +} static inline int xrep_attempt( diff --git a/fs/xfs/scrub/scrub.c b/fs/xfs/scrub/scrub.c index 7567dd5cad14..6fa9e3e5bab7 100644 --- a/fs/xfs/scrub/scrub.c +++ b/fs/xfs/scrub/scrub.c @@ -149,6 +149,18 @@ xchk_probe( if (xchk_should_terminate(sc, &error)) return error; + /* + * If the caller is probing to see if repair works but repair isn't + * built into the kernel, return EOPNOTSUPP because that's the signal + * that userspace expects. If online repair is built in, set the + * CORRUPT flag (without any of the usual tracing/logging) to force us + * into xrep_probe. + */ + if (xchk_could_repair(sc)) { + if (!IS_ENABLED(CONFIG_XFS_ONLINE_REPAIR)) + return -EOPNOTSUPP; + sc->sm->sm_flags |= XFS_SCRUB_OFLAG_CORRUPT; + } return 0; } From 6e33017c3276e3af7f79f61f3b3648e4a4c03d34 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 2 Feb 2025 16:50:14 -0800 Subject: [PATCH 2/6] xfs: fix data fork format filtering during inode repair Coverity noticed that xrep_dinode_bad_metabt_fork never runs because XFS_DINODE_FMT_META_BTREE is always filtered out in the mode selection switch of xrep_dinode_check_dfork. Metadata btrees are allowed only in the data forks of regular files, so add this case explicitly. I guess this got fubard during a refactoring prior to 6.13 and I didn't notice until now. :/ Coverity-id: 1617714 Signed-off-by: "Darrick J. Wong" Reviewed-by: Christoph Hellwig Signed-off-by: Carlos Maiolino --- fs/xfs/scrub/inode_repair.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/fs/xfs/scrub/inode_repair.c b/fs/xfs/scrub/inode_repair.c index 2f641b6d663e..13ff1c933cb8 100644 --- a/fs/xfs/scrub/inode_repair.c +++ b/fs/xfs/scrub/inode_repair.c @@ -1055,9 +1055,17 @@ xrep_dinode_check_dfork( return true; break; case S_IFREG: - if (fmt == XFS_DINODE_FMT_LOCAL) + switch (fmt) { + case XFS_DINODE_FMT_LOCAL: return true; - fallthrough; + case XFS_DINODE_FMT_EXTENTS: + case XFS_DINODE_FMT_BTREE: + case XFS_DINODE_FMT_META_BTREE: + break; + default: + return true; + } + break; case S_IFLNK: case S_IFDIR: switch (fmt) { From 9e00163c31676c6b43d2334fdf5b406232f42dee Mon Sep 17 00:00:00 2001 From: Lukas Herbolt Date: Mon, 3 Feb 2025 09:55:13 +0100 Subject: [PATCH 3/6] xfs: do not check NEEDSREPAIR if ro,norecovery mount. If there is corrutpion on the filesystem andxfs_repair fails to repair it. The last resort of getting the data is to use norecovery,ro mount. But if the NEEDSREPAIR is set the filesystem cannot be mounted. The flag must be cleared out manually using xfs_db, to get access to what left over of the corrupted fs. Signed-off-by: Lukas Herbolt Reviewed-by: Dave Chinner Reviewed-by: Eric Sandeen Signed-off-by: Carlos Maiolino --- fs/xfs/xfs_super.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index d92d7a07ea89..0055066fb1d9 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -1661,8 +1661,12 @@ xfs_fs_fill_super( #endif } - /* Filesystem claims it needs repair, so refuse the mount. */ - if (xfs_has_needsrepair(mp)) { + /* + * Filesystem claims it needs repair, so refuse the mount unless + * norecovery is also specified, in which case the filesystem can + * be mounted with no risk of further damage. + */ + if (xfs_has_needsrepair(mp) && !xfs_has_norecovery(mp)) { xfs_warn(mp, "Filesystem needs repair. Please run xfs_repair."); error = -EFSCORRUPTED; goto out_free_sb; From 9f0902091c332b2665951cfb970f60ae7cbdc0f3 Mon Sep 17 00:00:00 2001 From: Carlos Maiolino Date: Mon, 3 Feb 2025 14:04:57 +0100 Subject: [PATCH 4/6] xfs: Do not allow norecovery mount with quotacheck Mounting a filesystem that requires quota state changing will generate a transaction. We already check for a read-only device; we should do that for norecovery too. A quotacheck on a norecovery mount, and with the right log size, will cause the mount process to hang on: [<0>] xlog_grant_head_wait+0x5d/0x2a0 [xfs] [<0>] xlog_grant_head_check+0x112/0x180 [xfs] [<0>] xfs_log_reserve+0xe3/0x260 [xfs] [<0>] xfs_trans_reserve+0x179/0x250 [xfs] [<0>] xfs_trans_alloc+0x101/0x260 [xfs] [<0>] xfs_sync_sb+0x3f/0x80 [xfs] [<0>] xfs_qm_mount_quotas+0xe3/0x2f0 [xfs] [<0>] xfs_mountfs+0x7ad/0xc20 [xfs] [<0>] xfs_fs_fill_super+0x762/0xa50 [xfs] [<0>] get_tree_bdev_flags+0x131/0x1d0 [<0>] vfs_get_tree+0x26/0xd0 [<0>] vfs_cmd_create+0x59/0xe0 [<0>] __do_sys_fsconfig+0x4e3/0x6b0 [<0>] do_syscall_64+0x82/0x160 [<0>] entry_SYSCALL_64_after_hwframe+0x76/0x7e This is caused by a transaction running with bogus initialized head/tail I initially hit this while running generic/050, with random log sizes, but I managed to reproduce it reliably here with the steps below: mkfs.xfs -f -lsize=1025M -f -b size=4096 -m crc=1,reflink=1,rmapbt=1, -i sparse=1 /dev/vdb2 > /dev/null mount -o usrquota,grpquota,prjquota /dev/vdb2 /mnt xfs_io -x -c 'shutdown -f' /mnt umount /mnt mount -o ro,norecovery,usrquota,grpquota,prjquota /dev/vdb2 /mnt Last mount hangs up As we add yet another validation if quota state is changing, this also add a new helper named xfs_qm_validate_state_change(), factoring the quota state changes out of xfs_qm_newmount() to reduce cluttering within it. Signed-off-by: Carlos Maiolino Reviewed-by: Darrick J. Wong Signed-off-by: Carlos Maiolino --- fs/xfs/xfs_qm_bhv.c | 55 ++++++++++++++++++++++++++++++++------------- 1 file changed, 39 insertions(+), 16 deletions(-) diff --git a/fs/xfs/xfs_qm_bhv.c b/fs/xfs/xfs_qm_bhv.c index 37f1230e7584..245d754f382a 100644 --- a/fs/xfs/xfs_qm_bhv.c +++ b/fs/xfs/xfs_qm_bhv.c @@ -78,6 +78,28 @@ xfs_qm_statvfs( } } +STATIC int +xfs_qm_validate_state_change( + struct xfs_mount *mp, + uint uqd, + uint gqd, + uint pqd) +{ + int state; + + /* Is quota state changing? */ + state = ((uqd && !XFS_IS_UQUOTA_ON(mp)) || + (!uqd && XFS_IS_UQUOTA_ON(mp)) || + (gqd && !XFS_IS_GQUOTA_ON(mp)) || + (!gqd && XFS_IS_GQUOTA_ON(mp)) || + (pqd && !XFS_IS_PQUOTA_ON(mp)) || + (!pqd && XFS_IS_PQUOTA_ON(mp))); + + return state && + (xfs_dev_is_read_only(mp, "changing quota state") || + xfs_has_norecovery(mp)); +} + int xfs_qm_newmount( xfs_mount_t *mp, @@ -97,24 +119,25 @@ xfs_qm_newmount( } /* - * If the device itself is read-only, we can't allow - * the user to change the state of quota on the mount - - * this would generate a transaction on the ro device, - * which would lead to an I/O error and shutdown + * If the device itself is read-only and/or in norecovery + * mode, we can't allow the user to change the state of + * quota on the mount - this would generate a transaction + * on the ro device, which would lead to an I/O error and + * shutdown. */ - if (((uquotaondisk && !XFS_IS_UQUOTA_ON(mp)) || - (!uquotaondisk && XFS_IS_UQUOTA_ON(mp)) || - (gquotaondisk && !XFS_IS_GQUOTA_ON(mp)) || - (!gquotaondisk && XFS_IS_GQUOTA_ON(mp)) || - (pquotaondisk && !XFS_IS_PQUOTA_ON(mp)) || - (!pquotaondisk && XFS_IS_PQUOTA_ON(mp))) && - xfs_dev_is_read_only(mp, "changing quota state")) { - xfs_warn(mp, "please mount with%s%s%s%s.", - (!quotaondisk ? "out quota" : ""), - (uquotaondisk ? " usrquota" : ""), - (gquotaondisk ? " grpquota" : ""), - (pquotaondisk ? " prjquota" : "")); + if (xfs_qm_validate_state_change(mp, uquotaondisk, + gquotaondisk, pquotaondisk)) { + + if (xfs_has_metadir(mp)) + xfs_warn(mp, + "metadir enabled, please mount without any quota mount options"); + else + xfs_warn(mp, "please mount with%s%s%s%s.", + (!quotaondisk ? "out quota" : ""), + (uquotaondisk ? " usrquota" : ""), + (gquotaondisk ? " grpquota" : ""), + (pquotaondisk ? " prjquota" : "")); return -EPERM; } From 3cd6a8056f5a2e794c42fc2114ee2611e358b357 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 6 Feb 2025 07:15:01 +0100 Subject: [PATCH 5/6] xfs: rename xfs_iomap_swapfile_activate to xfs_vm_swap_activate Match the method name and the naming convention or address_space operations. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Reviewed-by: Dave Chinner Signed-off-by: Carlos Maiolino --- fs/xfs/xfs_aops.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 67877c36ed11..a80608e82c9b 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -528,7 +528,7 @@ xfs_vm_readahead( } static int -xfs_iomap_swapfile_activate( +xfs_vm_swap_activate( struct swap_info_struct *sis, struct file *swap_file, sector_t *span) @@ -549,11 +549,11 @@ const struct address_space_operations xfs_address_space_operations = { .migrate_folio = filemap_migrate_folio, .is_partially_uptodate = iomap_is_partially_uptodate, .error_remove_folio = generic_error_remove_folio, - .swap_activate = xfs_iomap_swapfile_activate, + .swap_activate = xfs_vm_swap_activate, }; const struct address_space_operations xfs_dax_aops = { .writepages = xfs_dax_writepages, .dirty_folio = noop_dirty_folio, - .swap_activate = xfs_iomap_swapfile_activate, + .swap_activate = xfs_vm_swap_activate, }; From 2d873efd174bae9005776937d5ac6a96050266db Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 6 Feb 2025 07:15:00 +0100 Subject: [PATCH 6/6] xfs: flush inodegc before swapon Fix the brand new xfstest that tries to swapon on a recently unshared file and use the chance to document the other bit of magic in this function. The big comment is taken from a mailinglist post by Dave Chinner. Fixes: 5e672cd69f0a53 ("xfs: introduce xfs_inodegc_push()") Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Reviewed-by: Dave Chinner Signed-off-by: Carlos Maiolino --- fs/xfs/xfs_aops.c | 35 ++++++++++++++++++++++++++++++++++- 1 file changed, 34 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index a80608e82c9b..6d9965b546cb 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -19,6 +19,7 @@ #include "xfs_reflink.h" #include "xfs_errortag.h" #include "xfs_error.h" +#include "xfs_icache.h" struct xfs_writepage_ctx { struct iomap_writepage_ctx ctx; @@ -533,7 +534,39 @@ xfs_vm_swap_activate( struct file *swap_file, sector_t *span) { - sis->bdev = xfs_inode_buftarg(XFS_I(file_inode(swap_file)))->bt_bdev; + struct xfs_inode *ip = XFS_I(file_inode(swap_file)); + + /* + * Swap file activation can race against concurrent shared extent + * removal in files that have been cloned. If this happens, + * iomap_swapfile_iter() can fail because it encountered a shared + * extent even though an operation is in progress to remove those + * shared extents. + * + * This race becomes problematic when we defer extent removal + * operations beyond the end of a syscall (i.e. use async background + * processing algorithms). Users think the extents are no longer + * shared, but iomap_swapfile_iter() still sees them as shared + * because the refcountbt entries for the extents being removed have + * not yet been updated. Hence the swapon call fails unexpectedly. + * + * The race condition is currently most obvious from the unlink() + * operation as extent removal is deferred until after the last + * reference to the inode goes away. We then process the extent + * removal asynchronously, hence triggers the "syscall completed but + * work not done" condition mentioned above. To close this race + * window, we need to flush any pending inodegc operations to ensure + * they have updated the refcountbt records before we try to map the + * swapfile. + */ + xfs_inodegc_flush(ip->i_mount); + + /* + * Direct the swap code to the correct block device when this file + * sits on the RT device. + */ + sis->bdev = xfs_inode_buftarg(ip)->bt_bdev; + return iomap_swapfile_activate(sis, swap_file, span, &xfs_read_iomap_ops); }