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author | Mikulas Patocka <mpatocka@redhat.com> | 2023-10-31 19:12:54 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-11-28 17:15:01 +0000 |
commit | e93ac6410de384421f6aca7fc1da4c4cd8e243ad (patch) | |
tree | 7660a06737cc1a09f5b00a5e9b975fe52d274588 | |
parent | 369f7c467211d0edabf587c7e452dc2b8f5f0bec (diff) | |
download | linux-stable-e93ac6410de384421f6aca7fc1da4c4cd8e243ad.tar.gz linux-stable-e93ac6410de384421f6aca7fc1da4c4cd8e243ad.tar.bz2 linux-stable-e93ac6410de384421f6aca7fc1da4c4cd8e243ad.zip |
dm crypt: account large pages in cc->n_allocated_pages
commit 9793c269da6cd339757de6ba5b2c8681b54c99af upstream.
The commit 5054e778fcd9c ("dm crypt: allocate compound pages if
possible") changed dm-crypt to use compound pages to improve
performance. Unfortunately, there was an oversight: the allocation of
compound pages was not accounted at all. Normal pages are accounted in
a percpu counter cc->n_allocated_pages and dm-crypt is limited to
allocate at most 2% of memory. Because compound pages were not
accounted at all, dm-crypt could allocate memory over the 2% limit.
Fix this by adding the accounting of compound pages, so that memory
consumption of dm-crypt is properly limited.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: 5054e778fcd9c ("dm crypt: allocate compound pages if possible")
Cc: stable@vger.kernel.org # v6.5+
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/md/dm-crypt.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index dc0463bf3c2c..0fadb656a215 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -1700,11 +1700,17 @@ retry: order = min(order, remaining_order); while (order > 0) { + if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) + + (1 << order) > dm_crypt_pages_per_client)) + goto decrease_order; pages = alloc_pages(gfp_mask | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP, order); - if (likely(pages != NULL)) + if (likely(pages != NULL)) { + percpu_counter_add(&cc->n_allocated_pages, 1 << order); goto have_pages; + } +decrease_order: order--; } @@ -1742,10 +1748,13 @@ static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */ bio_for_each_folio_all(fi, clone) { - if (folio_test_large(fi.folio)) + if (folio_test_large(fi.folio)) { + percpu_counter_sub(&cc->n_allocated_pages, + 1 << folio_order(fi.folio)); folio_put(fi.folio); - else + } else { mempool_free(&fi.folio->page, &cc->page_pool); + } } } } |