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Shutemov" , linux-kernel@vger.kernel.org, linux-mm@kvack.org References: From: Baolin Wang In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 14F4D1C0007 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: tfbegqgu7hck9dp4nsumz54yc3sw595z X-HE-Tag: 1724742870-263041 X-HE-Meta: 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 cmefgU0O qXvycYSPlFnQw3laQStvn1cp3hwLfEElA5aGAcgd2b3Ld3YdGKgeGO6jSCUuA6jqa3BOUFzIeXbSehrSW4QDHHQaSnTDagMVjAPR9LCei1l1a5GkXf0gQfk8go2lwzDDn9vtTaOzbpM9hz4pYNd44j9DeA9XAHPAUIHqNmNxBoGOAxSLpKLrAkSsibv1t7Tz89bR/lamGF5Wzj8B8ybzi7gIUJoIvQU8NxvTeKe0cUR7SXzNhnoAR/4eXMV2Xca/m1xoTeTWWEOh0hRs= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2024/8/26 06:42, Hugh Dickins wrote: > There has been a long-standing and very minor off-by-one, where > shmem_get_folio_gfp() decides if a large folio extends beyond i_size > far enough to leave a page or more for freeing later under pressure. > > This is not something needed for stable: but it will be proportionately > more significant as support for smaller large folios is added, and is > best fixed before duplicating the check in other places. > > Fixes: 779750d20b93 ("shmem: split huge pages beyond i_size under memory pressure") > Signed-off-by: Hugh Dickins LGTM. Feel free to add: Reviewed-by: Baolin Wang > --- > mm/shmem.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/shmem.c b/mm/shmem.c > index 85e3bd3e709e..37c300f69baf 100644 > --- a/mm/shmem.c > +++ b/mm/shmem.c > @@ -2326,7 +2326,7 @@ static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index, > alloced = true; > if (folio_test_large(folio) && > DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE) < > - folio_next_index(folio) - 1) { > + folio_next_index(folio)) { > struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb); > struct shmem_inode_info *info = SHMEM_I(inode); > /*