[PATCH] scsi: stex: fix MU_MAX_DELAY typecheck

[PATCH] scsi: stex: fix MU_MAX_DELAY typecheck

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

time_after() expects arguments of the same type, but gcc-13 changed the
way that typeof(MU_MAX_DELAY) is determined, causing a build warning as
'before + MU_MAX_DELAY * HZ' gets promoted to a 64-bit integer:

In file included from include/linux/bitops.h:7,
                 from include/linux/kernel.h:22,
                 from drivers/scsi/stex.c:13:
drivers/scsi/stex.c: In function 'stex_common_handshake':
include/linux/typecheck.h:12:25: error: comparison of distinct pointer types lacks a cast [-Werror]
   12 |         (void)(&__dummy == &__dummy2); \
      |                         ^~
include/linux/jiffies.h:106:10: note: in expansion of macro 'typecheck'
  106 |          typecheck(unsigned long, b) && \
      |          ^~~~~~~~~
drivers/scsi/stex.c:1035:29: note: in expansion of macro 'time_after'
 1035 |                         if (time_after(jiffies, before + MU_MAX_DELAY * HZ)) {

Change the enum definition so all values fit into an unsigned
32-bit number.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/scsi/stex.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/stex.c b/drivers/scsi/stex.c
index 8def242675ef..23462d3c9850 100644
--- a/drivers/scsi/stex.c
+++ b/drivers/scsi/stex.c
@@ -110,7 +110,7 @@ enum {
 	TASK_ATTRIBUTE_ORDERED			= 0x2,
 	TASK_ATTRIBUTE_ACA			= 0x4,
 
-	SS_STS_NORMAL				= 0x80000000,
+	SS_STS_NORMAL				= 0x80000000u,
 	SS_STS_DONE				= 0x40000000,
 	SS_STS_HANDSHAKE			= 0x20000000,
 
@@ -120,7 +120,7 @@ enum {
 
 	SS_I2H_REQUEST_RESET			= 0x2000,
 
-	SS_MU_OPERATIONAL			= 0x80000000,
+	SS_MU_OPERATIONAL			= 0x80000000u,
 
 	STEX_CDB_LENGTH				= 16,
 	STATUS_VAR_LEN				= 128,
@@ -173,7 +173,7 @@ enum {
 	ST_ADDITIONAL_MEM_MIN			= 0x80000,
 	PMIC_SHUTDOWN				= 0x0D,
 	PMIC_REUMSE					= 0x10,
-	ST_IGNORED					= -1,
+	ST_IGNORED					= -1u,
 	ST_NOTHANDLED				= 7,
 	ST_S3						= 3,
 	ST_S4						= 4,
-- 
2.39.0

Re: [PATCH] scsi: stex: fix MU_MAX_DELAY typecheck

[Bart Van Assche]

On 1/17/23 08:38, Arnd Bergmann wrote:
> @@ -173,7 +173,7 @@ enum {
>   	ST_ADDITIONAL_MEM_MIN			= 0x80000,
>   	PMIC_SHUTDOWN				= 0x0D,
>   	PMIC_REUMSE					= 0x10,
> -	ST_IGNORED					= -1,
> +	ST_IGNORED					= -1u,
>   	ST_NOTHANDLED				= 7,
>   	ST_S3						= 3,
>   	ST_S4						= 4,

 From drivers/scsi/stex.c:

int st_sleep_mic;

... st_sleep_mic == ST_IGNORED ...

Can changing ST_IGNORED from signed to unsigned break the stex driver?

Thanks,

Bart.