kernel/linux.git/fs/nfs, branch v6.6.131

pNFS: Fix a deadlock when returning a delegation during open()

2026-03-25T10:05:59+00:00

[ Upstream commit 857bf9056291a16785ae3be1d291026b2437fc48 ] Ben Coddington reports seeing a hang in the following stack trace: 0 [ffffd0b50e1774e0] __schedule at ffffffff9ca05415 1 [ffffd0b50e177548] schedule at ffffffff9ca05717 2 [ffffd0b50e177558] bit_wait at ffffffff9ca061e1 3 [ffffd0b50e177568] __wait_on_bit at ffffffff9ca05cfb 4 [ffffd0b50e1775c8] out_of_line_wait_on_bit at ffffffff9ca05ea5 5 [ffffd0b50e177618] pnfs_roc at ffffffffc154207b [nfsv4] 6 [ffffd0b50e1776b8] _nfs4_proc_delegreturn at ffffffffc1506586 [nfsv4] 7 [ffffd0b50e177788] nfs4_proc_delegreturn at ffffffffc1507480 [nfsv4] 8 [ffffd0b50e1777f8] nfs_do_return_delegation at ffffffffc1523e41 [nfsv4] 9 [ffffd0b50e177838] nfs_inode_set_delegation at ffffffffc1524a75 [nfsv4] 10 [ffffd0b50e177888] nfs4_process_delegation at ffffffffc14f41dd [nfsv4] 11 [ffffd0b50e1778a0] _nfs4_opendata_to_nfs4_state at ffffffffc1503edf [nfsv4] 12 [ffffd0b50e1778c0] _nfs4_open_and_get_state at ffffffffc1504e56 [nfsv4] 13 [ffffd0b50e177978] _nfs4_do_open at ffffffffc15051b8 [nfsv4] 14 [ffffd0b50e1779f8] nfs4_do_open at ffffffffc150559c [nfsv4] 15 [ffffd0b50e177a80] nfs4_atomic_open at ffffffffc15057fb [nfsv4] 16 [ffffd0b50e177ad0] nfs4_file_open at ffffffffc15219be [nfsv4] 17 [ffffd0b50e177b78] do_dentry_open at ffffffff9c09e6ea 18 [ffffd0b50e177ba8] vfs_open at ffffffff9c0a082e 19 [ffffd0b50e177bd0] dentry_open at ffffffff9c0a0935 The issue is that the delegreturn is being asked to wait for a layout return that cannot complete because a state recovery was initiated. The state recovery cannot complete until the open() finishes processing the delegations it was given. The solution is to propagate the existing flags that indicate a non-blocking call to the function pnfs_roc(), so that it knows not to wait in this situation. Reported-by: Benjamin Coddington Fixes: 29ade5db1293 ("pNFS: Wait on outstanding layoutreturns to complete in pnfs_roc()") Signed-off-by: Trond Myklebust [ Minor conflict resolved. ] Signed-off-by: Li hongliang <1468888505@139.com> Signed-off-by: Greg Kroah-Hartman

NFS: Fix a deadlock involving nfs_release_folio()

2026-03-25T10:05:59+00:00

[ Upstream commit cce0be6eb4971456b703aaeafd571650d314bcca ] Wang Zhaolong reports a deadlock involving NFSv4.1 state recovery waiting on kthreadd, which is attempting to reclaim memory by calling nfs_release_folio(). The latter cannot make progress due to state recovery being needed. It seems that the only safe thing to do here is to kick off a writeback of the folio, without waiting for completion, or else kicking off an asynchronous commit. Reported-by: Wang Zhaolong Fixes: 96780ca55e3c ("NFS: fix up nfs_release_folio() to try to release the page") Signed-off-by: Trond Myklebust [ Minor conflict resolved. ] Signed-off-by: Li hongliang <1468888505@139.com> Signed-off-by: Greg Kroah-Hartman

nfs: pass explicit offset/count to trace events

2026-03-25T10:05:59+00:00

[ Upstream commit fada32ed6dbc748f447c8d050a961b75d946055a ] nfs_folio_length is unsafe to use without having the folio locked and a check for a NULL ->f_mapping that protects against truncations and can lead to kernel crashes. E.g. when running xfstests generic/065 with all nfs trace points enabled. Follow the model of the XFS trace points and pass in an explіcit offset and length. This has the additional benefit that these values can be more accurate as some of the users touch partial folio ranges. Fixes: eb5654b3b89d ("NFS: Enable tracing of nfs_invalidate_folio() and nfs_launder_folio()") Reported-by: Chuck Lever Signed-off-by: Christoph Hellwig Signed-off-by: Anna Schumaker [ Minor conflict resolved. ] Signed-off-by: Li hongliang <1468888505@139.com> Signed-off-by: Greg Kroah-Hartman

fs/nfs: Fix readdir slow-start regression

2026-03-04T12:20:04+00:00

[ Upstream commit 42e7c876b182da65723700f6bc507a8aecb10d3b ] Commit 580f236737d1 ("NFS: Adjust the amount of readahead performed by NFS readdir") reduces the amount of readahead names caching done by the client. The downside of this approach is READDIR now may suffer from a slow-start issue, where initially it will fetch names that fit in a single page, then in 2, 4, 8 until the maximum supported transfer size (usually 1M). This patch tries to take a balanced approach between mitigating the slow-start issue still maintaining some efficiency gains. Fixes: 580f236737d1 ("NFS: Adjust the amount of readahead performed by NFS readdir") Signed-off-by: Sagi Grimberg Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin

pNFS: fix a missing wake up while waiting on NFS_LAYOUT_DRAIN

2026-03-04T12:20:03+00:00

[ Upstream commit 5248d8474e594d156bee1ed10339cc16e207a28b ] It is possible to have a task get stuck on waiting on the NFS_LAYOUT_DRAIN in the following scenario 1. cpu a: waiter test NFS_LAYOUT_DRAIN (1) and plh_outstanding (1) 2. cpu b: atomic_dec_and_test() -> clear bit -> wake up 3. cpu c: sets NFS_LAYOUT_DRAIN again 4. cpu a: calls wait_on_bit() sleeps forever. To expand on this we have say 2 outstanding pnfs write IO that get ESTALE which causes both to call pnfs_destroy_layout() and set the NFS_LAYOUT_DRAIN bit but the 1st one doesn't call the pnfs_put_layout_hdr() yet (as that would prevent the 2nd ESTALE write from trying to call pnfs_destroy_layout()). If the 1st ESTALE write is the one that initially sets the NFS_LAYOUT_DRAIN so that new IO on this file initiates new LAYOUTGET. Another new write would find NFS_LAYOUT_DRAIN set and phl_outstanding>0 (step 1) and would wait_on_bit(). LAYOUTGET completes doing step 2. Now, the 2nd of ESTALE writes is calling pnfs_destory_layout() and set the NFS_LAYOUT_DRAIN bit (step 3). Finally, the waiting write wakes up to check the bit and goes back to sleep. The problem revolves around the fact that if NFS_LAYOUT_INVALID_STID was already set, it should not do the work of pnfs_mark_layout_stateid_invalid(), thus NFS_LAYOUT_DRAIN will not be set more than once for an invalid layout. Suggested-by: Trond Myklebust Fixes: 880265c77ac4 ("pNFS: Avoid a live lock condition in pnfs_update_layout()") Signed-off-by: Olga Kornievskaia Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin

pnfs/flexfiles: Fix memory leak in nfs4_ff_alloc_deviceid_node()

2026-01-30T09:27:22+00:00

[ Upstream commit 0c728083654f0066f5e10a1d2b0bd0907af19a58 ] In nfs4_ff_alloc_deviceid_node(), if the allocation for ds_versions fails, the function jumps to the out_scratch label without freeing the already allocated dsaddrs list, leading to a memory leak. Fix this by jumping to the out_err_drain_dsaddrs label, which properly frees the dsaddrs list before cleaning up other resources. Fixes: d67ae825a59d6 ("pnfs/flexfiles: Add the FlexFile Layout Driver") Signed-off-by: Zilin Guan Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

nfs_common: factor out nfs_errtbl and nfs_stat_to_errno

2026-01-17T15:30:00+00:00

[ Upstream commit 4806ded4c14c5e8fdc6ce885d83221a78c06a428 ] Common nfs_stat_to_errno() is used by both fs/nfs/nfs2xdr.c and fs/nfs/nfs3xdr.c Will also be used by fs/nfsd/localio.c Signed-off-by: Mike Snitzer Reviewed-by: Jeff Layton Reviewed-by: NeilBrown Signed-off-by: Anna Schumaker Stable-dep-of: c6c209ceb87f ("NFSD: Remove NFSERR_EAGAIN") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

NFS: Fix up the automount fs_context to use the correct cred

2026-01-17T15:29:55+00:00

[ Upstream commit a2a8fc27dd668e7562b5326b5ed2f1604cb1e2e9 ] When automounting, the fs_context should be fixed up to use the cred from the parent filesystem, since the operation is just extending the namespace. Authorisation to enter that namespace will already have been provided by the preceding lookup. Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

NFSv4: ensure the open stateid seqid doesn't go backwards

2026-01-17T15:29:55+00:00

[ Upstream commit 2e47c3cc64b44b0b06cd68c2801db92ff143f2b2 ] We have observed an NFSv4 client receiving a LOCK reply with a status of NFS4ERR_OLD_STATEID and subsequently retrying the LOCK request with an earlier seqid value in the stateid. As this was for a new lockowner, that would imply that nfs_set_open_stateid_locked() had updated the open stateid seqid with an earlier value. Looking at nfs_set_open_stateid_locked(), if the incoming seqid is out of sequence, the task will sleep on the state->waitq for up to 5 seconds. If the task waits for the full 5 seconds, then after finishing the wait it'll update the open stateid seqid with whatever value the incoming seqid has. If there are multiple waiters in this scenario, then the last one to perform said update may not be the one with the highest seqid. Add a check to ensure that the seqid can only be incremented, and add a tracepoint to indicate when old seqids are skipped. Signed-off-by: Scott Mayhew Reviewed-by: Benjamin Coddington Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

NFS: Fix inheritance of the block sizes when automounting

2026-01-11T14:21:37+00:00

[ Upstream commit 2b092175f5e301cdaa935093edfef2be9defb6df ] Only inherit the block sizes that were actually specified as mount parameters for the parent mount. Fixes: 62a55d088cd8 ("NFS: Additional refactoring for fs_context conversion") Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin