Disables the warning: kernel: order 10 >= 10, gfp 0x40c00 kernel: WARNING: CPU: 5 PID: 182 at mm/page_alloc.c:5630 __alloc_pages+0x1d7/0x3f0 kernel: process_compressed_read+0x6f/0x590 [dm_qcow2]
As with 1M clusters and in case of zstd compression the buffer size (clu_size + sizeof(ZSTD_DCtx) + ZSTD_BLOCKSIZE_MAX + clu_size + ZSTD_BLOCKSIZE_MAX + 64 = 2520776) can only fit into 4M (10-th order) allocation. Let's add a separate warning to make sure we don't exceede currently expected size of 4M. Note: According to Documentation/core-api/gfp_mask-from-fs-io.rst GFP_NOIO is not supported in vmalloc, so probably we don't have an option to switch to kvmalloc here. https://virtuozzo.atlassian.net/browse/VSTOR-94596 Signed-off-by: Pavel Tikhomirov <ptikhomi...@virtuozzo.com> Feature: dm-qcow2: ZSTD decompression -- v2: add warning for >4M allocation and note about kvmalloc --- drivers/md/dm-qcow2-map.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/md/dm-qcow2-map.c b/drivers/md/dm-qcow2-map.c index 6585f3fac6e7b..6e738bbff13e1 100644 --- a/drivers/md/dm-qcow2-map.c +++ b/drivers/md/dm-qcow2-map.c @@ -10,6 +10,7 @@ #include <linux/zlib.h> #include <linux/error-injection.h> #include <linux/zstd.h> +#include <linux/sizes.h> #include "dm.h" #include "dm-rq.h" @@ -3671,7 +3672,8 @@ static void process_compressed_read(struct qcow2 *qcow2, struct list_head *read_ dctxlen = zlib_inflate_workspacesize(); - buf = kmalloc(qcow2->clu_size + dctxlen, GFP_NOIO); + WARN_ON(qcow2->clu_size + dctxlen > SZ_4M); + buf = kmalloc(qcow2->clu_size + dctxlen, GFP_NOIO | __GFP_ORDER_NOWARN); if (!buf) { end_qios(read_list, BLK_STS_RESOURCE); return; -- 2.47.0 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
