On Sunday 21 August 2022 17:17:12 Armin Wolf wrote:
> When a SMM call takes very long to execute, then it definitely
> is a firmware bug which should be marked with FW_BUG.
> Also add the number of the buggy SMM call to the warning message
> so BIOS developers, etc immediately know which part of the SMM
> interface is buggy.
>
> Tested on a Dell Inspiron 3505.
>
> Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
Acked-by: Pali Rohár <pali@xxxxxxxxxx>
Ideally this change should be CCed to Dell BIOS developers :D (hehe)
> ---
> drivers/hwmon/dell-smm-hwmon.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
> index 1dab7591576a..f7bab1a91b93 100644
> --- a/drivers/hwmon/dell-smm-hwmon.c
> +++ b/drivers/hwmon/dell-smm-hwmon.c
> @@ -26,6 +26,7 @@
> #include <linux/module.h>
> #include <linux/mutex.h>
> #include <linux/platform_device.h>
> +#include <linux/printk.h>
> #include <linux/proc_fs.h>
> #include <linux/seq_file.h>
> #include <linux/slab.h>
> @@ -198,7 +199,7 @@ static int i8k_smm_func(void *par)
> eax, ebx, regs->eax & 0xffff, carry, duration);
>
> if (duration > DELL_SMM_MAX_DURATION)
> - pr_warn_once("SMM call took %lld usecs!\n", duration);
> + pr_warn_once(FW_BUG "SMM call 0x%.4x took %lld usecs!\n", eax, duration);
>
> if (carry || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
> return -EINVAL;
> --
> 2.30.2
>
