[PATCH RESEND] scsi: ultrastor: Use correct format identifier for kernel pointer

[PATCH RESEND] scsi: ultrastor: Use correct format identifier for kernel pointer

[William Breathitt Gray]

The 'bios_segment' member of a struct ultrastor_config is passed to the
sprintf function with a respective %05X format identifier. The
'bio_segment' member is a kernel pointer, but the %X format identifier
expects an int data type. A cast to int is correctly used to satisfy the
format identifier, but this assumes that the int data type is the same
size as the kernel pointer, which is not the case on several
architectures such as X86_64. This patch removes the int cast and
replaces the %05X format identifier with %pK in order to print the
'bio_segment' member regardless of architecture.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
---
 drivers/scsi/ultrastor.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/ultrastor.c b/drivers/scsi/ultrastor.c
index 14e0c40..2e99f98 100644
--- a/drivers/scsi/ultrastor.c
+++ b/drivers/scsi/ultrastor.c
@@ -670,12 +670,12 @@ static const char *ultrastor_info(struct Scsi_Host * shpnt)
       sprintf(buf, "UltraStor 24F SCSI @ Slot %u IRQ%u",
 	      config.slot, config.interrupt);
     else if (config.subversion)
-      sprintf(buf, "UltraStor 34F SCSI @ Port %03X BIOS %05X IRQ%u",
-	      config.port_address, (int)config.bios_segment,
+      sprintf(buf, "UltraStor 34F SCSI @ Port %03X BIOS %pK IRQ%u",
+	      config.port_address, config.bios_segment,
 	      config.interrupt);
     else
-      sprintf(buf, "UltraStor 14F SCSI @ Port %03X BIOS %05X IRQ%u DMA%u",
-	      config.port_address, (int)config.bios_segment,
+      sprintf(buf, "UltraStor 14F SCSI @ Port %03X BIOS %pK IRQ%u DMA%u",
+	      config.port_address, config.bios_segment,
 	      config.interrupt, config.dma_channel);
     return buf;
 }
-- 
2.7.3

Re: [PATCH RESEND] scsi: ultrastor: Use correct format identifier for kernel pointer

[James Bottomley]

On Sun, 2016-05-01 at 17:57 -0400, William Breathitt Gray wrote:
> The 'bios_segment' member of a struct ultrastor_config is passed to the
> sprintf function with a respective %05X format identifier. The
> 'bio_segment' member is a kernel pointer, but the %X format identifier
> expects an int data type. A cast to int is correctly used to satisfy the
> format identifier, but this assumes that the int data type is the same
> size as the kernel pointer, which is not the case on several
> architectures such as X86_64. This patch removes the int cast and
> replaces the %05X format identifier with %pK in order to print the
> 'bio_segment' member regardless of architecture.

But this statement is wrong: ultrastor only has seven possible hard
coded bios segment values, all under 20 bits, as it happens, that's why
the printk is %05X.  Unless you're proposing to alter values in the
static table, there's no point in changing the print, is there?  Are
you proposing to alter the static table values?

James

Re: [PATCH RESEND] scsi: ultrastor: Use correct format identifier for kernel pointer

[William Breathitt Gray]

On Sun, May 01, 2016 at 04:08:25PM -0700, James Bottomley wrote:
>On Sun, 2016-05-01 at 17:57 -0400, William Breathitt Gray wrote:
>> The 'bios_segment' member of a struct ultrastor_config is passed to the
>> sprintf function with a respective %05X format identifier. The
>> 'bio_segment' member is a kernel pointer, but the %X format identifier
>> expects an int data type. A cast to int is correctly used to satisfy the
>> format identifier, but this assumes that the int data type is the same
>> size as the kernel pointer, which is not the case on several
>> architectures such as X86_64. This patch removes the int cast and
>> replaces the %05X format identifier with %pK in order to print the
>> 'bio_segment' member regardless of architecture.
>
>But this statement is wrong: ultrastor only has seven possible hard
>coded bios segment values, all under 20 bits, as it happens, that's why
>the printk is %05X.  Unless you're proposing to alter values in the
>static table, there's no point in changing the print, is there?  Are
>you proposing to alter the static table values?
>
>James

I'm sorry, I didn't realize bios_segment values were all under 20 bits;
in which case they should all fit within the original 5 digit
hexadecimal print. Please ignore this patch then as it was a
misunderstanding on my part.

Thanks,

William Breathitt Gray

[PATCH RESEND] scsi: ultrastor: Use correct format identifier for kernel pointer

[William Breathitt Gray]

The 'bios_segment' member of a struct ultrastor_config is passed to the
sprintf function with a respective %05X format identifier. The
'bio_segment' member is a kernel pointer, but the %X format identifier
expects an int data type. A cast to int is correctly used to satisfy the
format identifier, but this assumes that the int data type is the same
size as the kernel pointer, which is not the case on several
architectures such as X86_64. This patch removes the int cast and
replaces the %05X format identifier with %pK in order to print the
'bio_segment' member regardless of architecture.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
---
 drivers/scsi/ultrastor.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/ultrastor.c b/drivers/scsi/ultrastor.c
index 14e0c40..2e99f98 100644
--- a/drivers/scsi/ultrastor.c
+++ b/drivers/scsi/ultrastor.c
@@ -670,12 +670,12 @@ static const char *ultrastor_info(struct Scsi_Host * shpnt)
       sprintf(buf, "UltraStor 24F SCSI @ Slot %u IRQ%u",
 	      config.slot, config.interrupt);
     else if (config.subversion)
-      sprintf(buf, "UltraStor 34F SCSI @ Port %03X BIOS %05X IRQ%u",
-	      config.port_address, (int)config.bios_segment,
+      sprintf(buf, "UltraStor 34F SCSI @ Port %03X BIOS %pK IRQ%u",
+	      config.port_address, config.bios_segment,
 	      config.interrupt);
     else
-      sprintf(buf, "UltraStor 14F SCSI @ Port %03X BIOS %05X IRQ%u DMA%u",
-	      config.port_address, (int)config.bios_segment,
+      sprintf(buf, "UltraStor 14F SCSI @ Port %03X BIOS %pK IRQ%u DMA%u",
+	      config.port_address, config.bios_segment,
 	      config.interrupt, config.dma_channel);
     return buf;
 }
-- 
2.7.3