linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH 1/1] memory: tegra: fix fdc test bug
@ 2017-04-07 17:28 Ben Dooks
  2017-04-07 17:43 ` Thierry Reding
  0 siblings, 1 reply; 3+ messages in thread
From: Ben Dooks @ 2017-04-07 17:28 UTC (permalink / raw)
  To: linux-kernel, swarren, thierry.reding, gnurou, linux-tegra, linux-kernel
  Cc: Ben Dooks

The fdc variable is a bool, taking the address of this will generally
produce true, thus skewing any users of the tegra_mc_set_latency_allowance
code.

Note, this does not seem to be producing a compiler warning. This was only
spotted as it meant a caller was seeing 3 times higher than expected
register results.

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
---
 drivers/memory/tegra/mc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/memory/tegra/mc.c b/drivers/memory/tegra/mc.c
index fb44d1741862..e20470736319 100644
--- a/drivers/memory/tegra/mc.c
+++ b/drivers/memory/tegra/mc.c
@@ -121,7 +121,7 @@ int tegra_mc_set_latency_allowance(int client_id, unsigned int bandwidth)
 
 	WARN_ON(client->id != client_id);
 
-	if (&client->fdc)
+	if (client->fdc)
 		atom_bytes = plat_mc->soc->atom_size_fdc;
 	else
 		atom_bytes = plat_mc->soc->atom_size;
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH 1/1] memory: tegra: fix fdc test bug
  2017-04-07 17:28 [PATCH 1/1] memory: tegra: fix fdc test bug Ben Dooks
@ 2017-04-07 17:43 ` Thierry Reding
  2017-04-07 21:54   ` Ben Dooks
  0 siblings, 1 reply; 3+ messages in thread
From: Thierry Reding @ 2017-04-07 17:43 UTC (permalink / raw)
  To: Ben Dooks; +Cc: linux-kernel, swarren, gnurou, linux-tegra, linux-kernel

[-- Attachment #1: Type: text/plain, Size: 635 bytes --]

On Fri, Apr 07, 2017 at 06:28:20PM +0100, Ben Dooks wrote:
> The fdc variable is a bool, taking the address of this will generally
> produce true, thus skewing any users of the tegra_mc_set_latency_allowance
> code.
> 
> Note, this does not seem to be producing a compiler warning. This was only
> spotted as it meant a caller was seeing 3 times higher than expected
> register results.
> 
> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
> ---
>  drivers/memory/tegra/mc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

What tree is this based on? I don't see this code anywhere in mainline.

Thierry

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH 1/1] memory: tegra: fix fdc test bug
  2017-04-07 17:43 ` Thierry Reding
@ 2017-04-07 21:54   ` Ben Dooks
  0 siblings, 0 replies; 3+ messages in thread
From: Ben Dooks @ 2017-04-07 21:54 UTC (permalink / raw)
  To: Thierry Reding; +Cc: linux-kernel, swarren, gnurou, linux-tegra, linux-kernel

On 2017-04-07 18:43, Thierry Reding wrote:
> On Fri, Apr 07, 2017 at 06:28:20PM +0100, Ben Dooks wrote:
>> The fdc variable is a bool, taking the address of this will generally
>> produce true, thus skewing any users of the 
>> tegra_mc_set_latency_allowance
>> code.
>> 
>> Note, this does not seem to be producing a compiler warning. This was 
>> only
>> spotted as it meant a caller was seeing 3 times higher than expected
>> register results.
>> 
>> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
>> ---
>>  drivers/memory/tegra/mc.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> What tree is this based on? I don't see this code anywhere in mainline.

Apologies, turns out this a vendor added function.

-- 
Ben

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2017-04-07 21:54 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-04-07 17:28 [PATCH 1/1] memory: tegra: fix fdc test bug Ben Dooks
2017-04-07 17:43 ` Thierry Reding
2017-04-07 21:54   ` Ben Dooks

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).