Reporting zones on a SCSI device sometimes fail with the following error.
[76248.516390] ata16.00: invalid transfer count 131328
[76248.523618] sd 15:0:0:0: [sda] REPORT ZONES start lba 536870912 failed
The error (from drivers/ata/libata-scsi.c ata_scsi_zbc_in_xlat())
indicates that buffer size is not aligned to SECTOR_SIZE.
This happens when the __vmalloc() failed. Consider we are reporting 4096
zones, then we will have "bufsize = roundup((4096 + 1) * 64,
SECTOR_SIZE)" = (513 * 512) = 262656. Then, __vmalloc() failure halven
the bufsize to 131328, which is no longer aligned to SECTOR_SIZE.
Use rounddown() to ensure the size is always aligned to SECTOR_SIZE and
fix the comment as well.
Fixes: 23a50861adda ("scsi: sd_zbc: Cleanup sd_zbc_alloc_report_buffer()")
Cc: stable@xxxxxxxxxxxxxxx # 5.5+
Signed-off-by: Naohiro Aota <naohiro.aota@xxxxxxx>
---
drivers/scsi/sd_zbc.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c
index 186b5ff52c3a..ea8b3f6ee5cd 100644
--- a/drivers/scsi/sd_zbc.c
+++ b/drivers/scsi/sd_zbc.c
@@ -154,8 +154,8 @@ static void *sd_zbc_alloc_report_buffer(struct scsi_disk *sdkp,
/*
* Report zone buffer size should be at most 64B times the number of
- * zones requested plus the 64B reply header, but should be at least
- * SECTOR_SIZE for ATA devices.
+ * zones requested plus the 64B reply header, but should be aligned
+ * to SECTOR_SIZE for ATA devices.
* Make sure that this size does not exceed the hardware capabilities.
* Furthermore, since the report zone command cannot be split, make
* sure that the allocated buffer can always be mapped by limiting the
@@ -174,7 +174,7 @@ static void *sd_zbc_alloc_report_buffer(struct scsi_disk *sdkp,
*buflen = bufsize;
return buf;
}
- bufsize >>= 1;
+ bufsize = rounddown(bufsize >> 1, SECTOR_SIZE);
}
return NULL;
--
2.33.0
