cherry-pick fix for data corruption

[zfsonlinux.git] / debian / patches / 0014-zpool-status-tighten-bounds-for-noalloc-stat-availab.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Thomas Lamprecht <t.lamprecht@proxmox.com>
Date: Sun, 12 Nov 2023 15:52:25 +0100
Subject: [PATCH] zpool status: tighten bounds for noalloc stat availabillity

When running zfs 2.2.0 userspace utilities with a kernel that still
has 2.1.13 modules zpool status adds `(non-allocating)` next to the
disk name of a single-disk pool.

The reason for this seems to be that the patch adding the `vs_pspace` field was
backported, but the one adding `vs_noalloc` was not.

Itself that is not a problem, but in 2.2 `noalloc` was added before `psspace`,
so the struct layout between 2.1.13 and 2.2.0 do NOT match anymore...

I.e., the struct looks like the following at the end for ZFS 2.1.x:

```
typedef struct vdev_stat {
    hrtime_t        vs_timestamp;           /* time since vdev load */
    // snip
    uint64_t        vs_logical_ashift;      /* vdev_logical_ashift  */
    uint64_t        vs_physical_ashift;     /* vdev_physical_ashift */
    uint64_t        vs_pspace;              /* physical capacity */
} vdev_stat_t;
```

And like the following on ZFS 2.2.x:
```
typedef struct vdev_stat {
    hrtime_t        vs_timestamp;           /* time since vdev load */
    // snip
    uint64_t        vs_logical_ashift;      /* vdev_logical_ashift  */
    uint64_t        vs_physical_ashift;     /* vdev_physical_ashift */
    uint64_t        vs_noalloc;             /* allocations halted?  */
    uint64_t        vs_pspace;              /* physical capacity */
} vdev_stat_t;
```

Resulting in 2.2.x user-space tooling interpreting the `vs_pspace` field from
the 2.1.x kernel module as `vs_noalloc` field.

For now, work-around that discrepancy by coupling the availability of
the vs_noalloc field with the one of the vs_pspace one, as when both
are returned from the module we can be sure that our struct layout
matches again.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
 cmd/zpool/zpool_main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/cmd/zpool/zpool_main.c b/cmd/zpool/zpool_main.c
index 5507f9d3f..98970abfe 100644
--- a/cmd/zpool/zpool_main.c
+++ b/cmd/zpool/zpool_main.c
@@ -2478,7 +2478,8 @@ print_status_config(zpool_handle_t *zhp, status_cbdata_t *cb, const char *name,
 
 	if (vs->vs_scan_removing != 0) {
 		(void) printf(gettext("  (removing)"));
-	} else if (VDEV_STAT_VALID(vs_noalloc, vsc) && vs->vs_noalloc != 0) {
+	} else if (VDEV_STAT_VALID(vs_pspace, vsc)
+		       && VDEV_STAT_VALID(vs_noalloc, vsc) && vs->vs_noalloc != 0) {
 		(void) printf(gettext("  (non-allocating)"));
 	}