On Sun, Oct 22, 2023 at 09:58:26AM -0700, Guenter Roeck wrote:
On 10/14/23 02:12, Darren Hart wrote:
On Tue, Sep 26, 2023 at 05:45:13AM -0700, Guenter Roeck wrote:
On Thu, Sep 21, 2023 at 02:02:36AM -0700, Darren Hart wrote:
Commit abd3ac7902fb ("watchdog: sbsa: Support architecture version 1") introduced new timer math for watchdog revision 1 with the 48 bit offset register.
The gwdt->clk and timeout are u32, but the argument being calculated is u64. Without a cast, the compiler performs u32 operations, truncating intermediate steps, resulting in incorrect values.
A watchdog revision 1 implementation with a gwdt->clk of 1GHz and a timeout of 600s writes 3647256576 to the one shot watchdog instead of 300000000000, resulting in the watchdog firing in 3.6s instead of 600s.
Force u64 math by casting the first argument (gwdt->clk) as a u64. Make the order of operations explicit with parenthesis.
Fixes: abd3ac7902fb ("watchdog: sbsa: Support architecture version 1") Reported-by: Vanshidhar Konda vanshikonda@os.amperecomputing.com Signed-off-by: Darren Hart darren@os.amperecomputing.com Cc: Wim Van Sebroeck wim@linux-watchdog.org Cc: Guenter Roeck linux@roeck-us.net Cc: linux-watchdog@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: stable@vger.kernel.org # 5.14.x
Reviewed-by: Guenter Roeck linux@roeck-us.net
Guenter or Wim, I haven't seen this land in the RCs or in next yet. Have you already picked it up? Anything more needed from me?
Thanks,
Sorry, I am suffering from what I can only describe as a severe case of maintainer/reviewer PTSD, and I have yet to find a way of dealing with that.
I'm sorry to hear it Guenter, it can be a thankless slog of a treadmill sometimes. I found having a co-maintainer a huge help to even out the human factors while maintaining the x86 platform drivers (in the before times).
In the short term, should I ask if one of the Arm maintainers would be willing to pick this patch up?
Thanks,