From d5b4310993947b0c561d4d648ca96cd464c58f57 Mon Sep 17 00:00:00 2001 From: Steve Siwinski Date: Thu, 8 May 2025 16:01:22 -0400 Subject: [PATCH] scsi: sd_zbc: block: Respect bio vector limits for REPORT ZONES buffer commit e8007fad5457ea547ca63bb011fdb03213571c7e upstream. The REPORT ZONES buffer size is currently limited by the HBA's maximum segment count to ensure the buffer can be mapped. However, the block layer further limits the number of iovec entries to 1024 when allocating a bio. To avoid allocation of buffers too large to be mapped, further restrict the maximum buffer size to BIO_MAX_INLINE_VECS. Replace the UIO_MAXIOV symbolic name with the more contextually appropriate BIO_MAX_INLINE_VECS. Fixes: b091ac616846 ("sd_zbc: Fix report zones buffer allocation") Cc: stable@vger.kernel.org Signed-off-by: Steve Siwinski Link: https://lore.kernel.org/r/20250508200122.243129-1-ssiwinski@atto.com Reviewed-by: Damien Le Moal Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman --- block/bio.c | 2 +- drivers/scsi/sd_zbc.c | 6 +++++- include/linux/bio.h | 1 + 3 files changed, 7 insertions(+), 2 deletions(-) diff --git a/block/bio.c b/block/bio.c index a7323d567c798..7e2ce61bf2479 100644 --- a/block/bio.c +++ b/block/bio.c @@ -576,7 +576,7 @@ struct bio *bio_kmalloc(unsigned short nr_vecs, gfp_t gfp_mask) { struct bio *bio; - if (nr_vecs > UIO_MAXIOV) + if (nr_vecs > BIO_MAX_INLINE_VECS) return NULL; return kmalloc(struct_size(bio, bi_inline_vecs, nr_vecs), gfp_mask); } diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c index 4c78288ffa72f..5fc6bf95258c6 100644 --- a/drivers/scsi/sd_zbc.c +++ b/drivers/scsi/sd_zbc.c @@ -197,6 +197,7 @@ static void *sd_zbc_alloc_report_buffer(struct scsi_disk *sdkp, unsigned int nr_zones, size_t *buflen) { struct request_queue *q = sdkp->disk->queue; + unsigned int max_segments; size_t bufsize; void *buf; @@ -208,12 +209,15 @@ static void *sd_zbc_alloc_report_buffer(struct scsi_disk *sdkp, * Furthermore, since the report zone command cannot be split, make * sure that the allocated buffer can always be mapped by limiting the * number of pages allocated to the HBA max segments limit. + * Since max segments can be larger than the max inline bio vectors, + * further limit the allocated buffer to BIO_MAX_INLINE_VECS. */ nr_zones = min(nr_zones, sdkp->zone_info.nr_zones); bufsize = roundup((nr_zones + 1) * 64, SECTOR_SIZE); bufsize = min_t(size_t, bufsize, queue_max_hw_sectors(q) << SECTOR_SHIFT); - bufsize = min_t(size_t, bufsize, queue_max_segments(q) << PAGE_SHIFT); + max_segments = min(BIO_MAX_INLINE_VECS, queue_max_segments(q)); + bufsize = min_t(size_t, bufsize, max_segments << PAGE_SHIFT); while (bufsize >= SECTOR_SIZE) { buf = kvzalloc(bufsize, GFP_KERNEL | __GFP_NORETRY); diff --git a/include/linux/bio.h b/include/linux/bio.h index 2b9fc5edf49d6..00ab98ce1d438 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -11,6 +11,7 @@ #include #define BIO_MAX_VECS 256U +#define BIO_MAX_INLINE_VECS UIO_MAXIOV static inline unsigned int bio_max_segs(unsigned int nr_segs) {