From: Dave Chinner <dchinner@xxxxxxxxxx>
Source kernel commit: de631e1a8b71017b8a12b57d07db82e4052555af
Pankaj Raghav reported that when filesystem block size is larger
than page size, the xattr code can use kmalloc() for high order
allocations. This triggers a useless warning in the allocator as it
is a __GFP_NOFAIL allocation here:
static inline
struct page *rmqueue(struct zone *preferred_zone,
struct zone *zone, unsigned int order,
gfp_t gfp_flags, unsigned int alloc_flags,
int migratetype)
{
struct page *page;
/*
* We most definitely don't want callers attempting to
* allocate greater than order-1 page units with __GFP_NOFAIL.
*/
>>>> WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
...
Fix this by changing all these call sites to use kvmalloc(), which
will strip the NOFAIL from the kmalloc attempt and if that fails
will do a __GFP_NOFAIL vmalloc().
This is not an issue that productions systems will see as
filesystems with block size > page size cannot be mounted by the
kernel; Pankaj is developing this functionality right now.
Reported-by: Pankaj Raghav <kernel@xxxxxxxxxxxxxxxx>
Fixes: f078d4ea8276 ("xfs: convert kmem_alloc() to kmalloc()")
Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240822135018.1931258-8-kernel@xxxxxxxxxxxxxxxx
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Reviewed-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Acked-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Reviewed-by: Daniel Gomez <da.gomez@xxxxxxxxxxx>
Reviewed-by: Dave Chinner <dchinner@xxxxxxxxxx>
Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
---
include/kmem.h | 6 ++++++
libxfs/xfs_attr_leaf.c | 15 ++++++---------
2 files changed, 12 insertions(+), 9 deletions(-)
diff --git a/include/kmem.h b/include/kmem.h
index 8dfb2fb0b45020..8739d824008e2a 100644
--- a/include/kmem.h
+++ b/include/kmem.h
@@ -59,12 +59,18 @@ static inline void *kmalloc(size_t size, gfp_t flags)
}
#define kzalloc(size, gfp) kvmalloc((size), (gfp) | __GFP_ZERO)
+#define kvzalloc(size, gfp) kzalloc((size), (gfp))
static inline void kfree(const void *ptr)
{
free((void *)ptr);
}
+static inline void kvfree(const void *ptr)
+{
+ kfree(ptr);
+}
+
__attribute__((format(printf,2,3)))
char *kasprintf(gfp_t gfp, const char *fmt, ...);
diff --git a/libxfs/xfs_attr_leaf.c b/libxfs/xfs_attr_leaf.c
index 97b71b6500bdc9..db2e48d719d36f 100644
--- a/libxfs/xfs_attr_leaf.c
+++ b/libxfs/xfs_attr_leaf.c
@@ -1135,10 +1135,7 @@ xfs_attr3_leaf_to_shortform(
trace_xfs_attr_leaf_to_sf(args);
- tmpbuffer = kmalloc(args->geo->blksize, GFP_KERNEL | __GFP_NOFAIL);
- if (!tmpbuffer)
- return -ENOMEM;
-
+ tmpbuffer = kvmalloc(args->geo->blksize, GFP_KERNEL | __GFP_NOFAIL);
memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
leaf = (xfs_attr_leafblock_t *)tmpbuffer;
@@ -1202,7 +1199,7 @@ xfs_attr3_leaf_to_shortform(
error = 0;
out:
- kfree(tmpbuffer);
+ kvfree(tmpbuffer);
return error;
}
@@ -1610,7 +1607,7 @@ xfs_attr3_leaf_compact(
trace_xfs_attr_leaf_compact(args);
- tmpbuffer = kmalloc(args->geo->blksize, GFP_KERNEL | __GFP_NOFAIL);
+ tmpbuffer = kvmalloc(args->geo->blksize, GFP_KERNEL | __GFP_NOFAIL);
memcpy(tmpbuffer, bp->b_addr, args->geo->blksize);
memset(bp->b_addr, 0, args->geo->blksize);
leaf_src = (xfs_attr_leafblock_t *)tmpbuffer;
@@ -1648,7 +1645,7 @@ xfs_attr3_leaf_compact(
*/
xfs_trans_log_buf(trans, bp, 0, args->geo->blksize - 1);
- kfree(tmpbuffer);
+ kvfree(tmpbuffer);
}
/*
@@ -2327,7 +2324,7 @@ xfs_attr3_leaf_unbalance(
struct xfs_attr_leafblock *tmp_leaf;
struct xfs_attr3_icleaf_hdr tmphdr;
- tmp_leaf = kzalloc(state->args->geo->blksize,
+ tmp_leaf = kvzalloc(state->args->geo->blksize,
GFP_KERNEL | __GFP_NOFAIL);
/*
@@ -2368,7 +2365,7 @@ xfs_attr3_leaf_unbalance(
}
memcpy(save_leaf, tmp_leaf, state->args->geo->blksize);
savehdr = tmphdr; /* struct copy */
- kfree(tmp_leaf);
+ kvfree(tmp_leaf);
}
xfs_attr3_leaf_hdr_to_disk(state->args->geo, save_leaf, &savehdr);
