Merge pull request #270445 from adamcstephens/backport-270275-to-release-23.11

From 3ba4ff328ab001d88d7714087d8a89687bc68312 Mon Sep 17 00:00:00 2001

From: Andrew Marshall <andrew@johnandrewmarshall.com>

Date: Sun, 26 Nov 2023 12:46:18 -0500

Subject: [PATCH] Disable zfs_dmu_offset_next_sync tunable by default

This helps mitigate a data corruption bug. This was previously defaulted

to zero, so doing so seems safe.

See https://github.com/openzfs/zfs/issues/11900

See https://github.com/openzfs/zfs/issues/15526

---

 man/man4/zfs.4   | 2 +-

 module/zfs/dmu.c | 2 +-

 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/man/man4/zfs.4 b/man/man4/zfs.4

index 4ec52a2fb..2a69a8f54 100644

--- a/man/man4/zfs.4

+++ b/man/man4/zfs.4

@@ -1660,7 +1660,7 @@ Allow no-operation writes.

 The occurrence of nopwrites will further depend on other pool properties

 .Pq i.a. the checksumming and compression algorithms .

 .

-.It Sy zfs_dmu_offset_next_sync Ns = Ns Sy 1 Ns | Ns 0 Pq int

+.It Sy zfs_dmu_offset_next_sync Ns = Ns Sy 0 Ns | Ns 1 Pq int

 Enable forcing TXG sync to find holes.

 When enabled forces ZFS to sync data when

 .Sy SEEK_HOLE No or Sy SEEK_DATA

diff --git a/module/zfs/dmu.c b/module/zfs/dmu.c

index ddb29020b..5d37b6f92 100644

--- a/module/zfs/dmu.c

+++ b/module/zfs/dmu.c

@@ -82,7 +82,7 @@ static uint_t zfs_per_txg_dirty_frees_percent = 30;

  * Disabling this option will result in holes never being reported in dirty

  * files which is always safe.

  */

-static int zfs_dmu_offset_next_sync = 1;

+static int zfs_dmu_offset_next_sync = 0;

 /*

  * Limit the amount we can prefetch with one call to this amount.  This

-- 

2.42.0

, stdenv

, linuxKernel

, removeLinuxDRM ? false

, fetchpatch

, ...

} @ args:

  # this package should point to the latest release.

  version = "2.2.1";

  extraPatches = [

    ./patches/disable-zfs-dmu-offset-next-sync-by-default-v2-2.patch

  ];

  sha256 = "sha256-2Q/Nhp3YKgMCLPNRNBq5r9U4GeuYlWMWAsjsQy3vFW4=";

}

  sha256 = "sha256-2Q/Nhp3YKgMCLPNRNBq5r9U4GeuYlWMWAsjsQy3vFW4=";

  isUnstable = true;

  extraPatches = [

    ./patches/disable-zfs-dmu-offset-next-sync-by-default-v2-2.patch

  ];

}