2021-03-30 07:22:32

by Sergei Trofimovich

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Subject: [PATCH v2 2/3] hpsa: fix boot on ia64 (atomic_t alignment)

The failure initially observed as boot failure on rx3600 ia64 machine
with RAID bus controller: Hewlett-Packard Company Smart Array P600:

kernel unaligned access to 0xe000000105dd8b95, ip=0xa000000100b87551
kernel unaligned access to 0xe000000105dd8e95, ip=0xa000000100b87551
hpsa 0000:14:01.0: Controller reports max supported commands of 0 Using 16 instead. Ensure that firmware is up to date.
swapper/0[1]: error during unaligned kernel access

Here unaligned access comes from 'struct CommandList' that happens
to be packed. The change f749d8b7a ("scsi: hpsa: Correct dev cmds
outstanding for retried cmds") introduced unexpected padding and
un-aligned atomic_t from natural alignment to something else.

This change removes packing annotation from struct not intended to be
sent to controller as is. This restores natural `atomic_t` alignment.

The change is tested on the same rx3600 machine.

CC: [email protected]
CC: [email protected]
CC: [email protected]
CC: [email protected]
CC: Joe Szczypek <[email protected]>
CC: Scott Benesh <[email protected]>
CC: Scott Teel <[email protected]>
CC: Tomas Henzl <[email protected]>
CC: "Martin K. Petersen" <[email protected]>
CC: Don Brace <[email protected]>
Reported-by: John Paul Adrian Glaubitz <[email protected]>
Suggested-by: Don Brace <[email protected]>
Fixes: f749d8b7a "scsi: hpsa: Correct dev cmds outstanding for retried cmds"
Signed-off-by: Sergei Trofimovich <[email protected]>
---
drivers/scsi/hpsa_cmd.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/hpsa_cmd.h b/drivers/scsi/hpsa_cmd.h
index 280e933d27e7..885b1f1fb20a 100644
--- a/drivers/scsi/hpsa_cmd.h
+++ b/drivers/scsi/hpsa_cmd.h
@@ -452,7 +452,7 @@ struct CommandList {
bool retry_pending;
struct hpsa_scsi_dev_t *device;
atomic_t refcount; /* Must be last to avoid memset in hpsa_cmd_init() */
-} __packed __aligned(COMMANDLIST_ALIGNMENT);
+} __aligned(COMMANDLIST_ALIGNMENT);

/* Max S/G elements in I/O accelerator command */
#define IOACCEL1_MAXSGENTRIES 24
--
2.31.1