2023-03-09 05:34:07

by Gao Xiang

Subject: [PATCH 1/2] erofs: Revert "erofs: fix kvcalloc() misuse with __GFP_NOFAIL"

Let's revert commit 12724ba38992 ("erofs: fix kvcalloc() misuse with
__GFP_NOFAIL") since kvmalloc() already supports __GFP_NOFAIL in commit
a421ef303008 ("mm: allow !GFP_KERNEL allocations for kvmalloc"). So
the original fix was wrong.

Actually there was some issue as [1] discussed, so before that mm fix
is landed, the warn could still happen but applying this commit first
will cause less.

[1] https://lore.kernel.org/r/[email protected]
Fixes: 12724ba38992 ("erofs: fix kvcalloc() misuse with __GFP_NOFAIL")
Signed-off-by: Gao Xiang <[email protected]>
---
fs/erofs/zdata.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 3247d2422bea..f1708c77a991 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -1312,12 +1312,12 @@ static int z_erofs_decompress_pcluster(struct z_erofs_decompress_backend *be,

if (!be->decompressed_pages)
be->decompressed_pages =
- kcalloc(be->nr_pages, sizeof(struct page *),
- GFP_KERNEL | __GFP_NOFAIL);
+ kvcalloc(be->nr_pages, sizeof(struct page *),
+ GFP_KERNEL | __GFP_NOFAIL);
if (!be->compressed_pages)
be->compressed_pages =
- kcalloc(pclusterpages, sizeof(struct page *),
- GFP_KERNEL | __GFP_NOFAIL);
+ kvcalloc(pclusterpages, sizeof(struct page *),
+ GFP_KERNEL | __GFP_NOFAIL);

z_erofs_parse_out_bvecs(be);
err2 = z_erofs_parse_in_bvecs(be, &overlapped);
@@ -1365,7 +1365,7 @@ static int z_erofs_decompress_pcluster(struct z_erofs_decompress_backend *be,
}
if (be->compressed_pages < be->onstack_pages ||
be->compressed_pages >= be->onstack_pages + Z_EROFS_ONSTACK_PAGES)
- kfree(be->compressed_pages);
+ kvfree(be->compressed_pages);
z_erofs_fill_other_copies(be, err);

for (i = 0; i < be->nr_pages; ++i) {
@@ -1384,7 +1384,7 @@ static int z_erofs_decompress_pcluster(struct z_erofs_decompress_backend *be,
}

if (be->decompressed_pages != be->onstack_pages)
- kfree(be->decompressed_pages);
+ kvfree(be->decompressed_pages);

pcl->length = 0;
pcl->partial = true;
--
2.24.4

2023-03-09 14:30:29

by Chao Yu

Subject: Re: [PATCH 1/2] erofs: Revert "erofs: fix kvcalloc() misuse with __GFP_NOFAIL"

On 2023/3/9 13:31, Gao Xiang wrote:
> Let's revert commit 12724ba38992 ("erofs: fix kvcalloc() misuse with
> __GFP_NOFAIL") since kvmalloc() already supports __GFP_NOFAIL in commit
> a421ef303008 ("mm: allow !GFP_KERNEL allocations for kvmalloc"). So
> the original fix was wrong.
>
> Actually there was some issue as [1] discussed, so before that mm fix
> is landed, the warn could still happen but applying this commit first
> will cause less.
>
> [1] https://lore.kernel.org/r/[email protected]
> Fixes: 12724ba38992 ("erofs: fix kvcalloc() misuse with __GFP_NOFAIL")
> Signed-off-by: Gao Xiang <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,