lkml.org 
[lkml]   [2022]   [Dec]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
SubjectRe: [PATCH] drm/amd/pm: avoid large variable on kernel stack
From
Le 15/12/2022 à 17:36, Arnd Bergmann a écrit :
> From: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
>
> The activity_monitor_external[] array is too big to fit on the
> kernel stack, resulting in this warning with clang:
>
> drivers/gpu/drm/amd/amdgpu/../pm/swsmu/smu13/smu_v13_0_7_ppt.c:1438:12: error: stack frame size (1040) exceeds limit (1024) in 'smu_v13_0_7_get_power_profile_mode' [-Werror,-Wframe-larger-than]
>
> Use dynamic allocation instead. It should also be possible to
> have single element here instead of the array, but this seems
> easier.
>
> Fixes: 334682ae8151 ("drm/amd/pm: enable workload type change on smu_v13_0_7")
> Signed-off-by: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
> ---
> .../drm/amd/pm/swsmu/smu13/smu_v13_0_7_ppt.c | 21 ++++++++++++++-----
> 1 file changed, 16 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_7_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_7_ppt.c
> index c270f94a1b86..7eba854e09ec 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_7_ppt.c
> +++ b/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_7_ppt.c
> @@ -1439,7 +1439,7 @@ static int smu_v13_0_7_get_power_limit(struct smu_context *smu,
>
> static int smu_v13_0_7_get_power_profile_mode(struct smu_context *smu, char *buf)
> {
> - DpmActivityMonitorCoeffIntExternal_t activity_monitor_external[PP_SMC_POWER_PROFILE_COUNT];
> + DpmActivityMonitorCoeffIntExternal_t *activity_monitor_external;
> uint32_t i, j, size = 0;
> int16_t workload_type = 0;
> int result = 0;
> @@ -1447,6 +1447,12 @@ static int smu_v13_0_7_get_power_profile_mode(struct smu_context *smu, char *buf
> if (!buf)
> return -EINVAL;
>
> + activity_monitor_external = kcalloc(sizeof(activity_monitor_external),

Hi,

Before, 'activity_monitor_external' was not initialized.
Maybe kcalloc() is enough?

sizeof(*activity_monitor_external)?
~~~~

> + PP_SMC_POWER_PROFILE_COUNT,
> + GFP_KERNEL);
> + if (!activity_monitor_external)
> + return -ENOMEM;
> +
> size += sysfs_emit_at(buf, size, " ");
> for (i = 0; i <= PP_SMC_POWER_PROFILE_WINDOW3D; i++)

Unrelated, but wouldn't it be more straightforward with "<
PP_SMC_POWER_PROFILE_COUNT"?

> size += sysfs_emit_at(buf, size, "%-14s%s", amdgpu_pp_profile_name[i],
> @@ -1459,15 +1465,17 @@ static int smu_v13_0_7_get_power_profile_mode(struct smu_context *smu, char *buf
> workload_type = smu_cmn_to_asic_specific_index(smu,
> CMN2ASIC_MAPPING_WORKLOAD,
> i);
> - if (workload_type < 0)
> - return -EINVAL;
> + if (workload_type < 0) {
> + result = -EINVAL;
> + goto out;
> + }
>
> result = smu_cmn_update_table(smu,
> SMU_TABLE_ACTIVITY_MONITOR_COEFF, workload_type,
> (void *)(&activity_monitor_external[i]), false);
> if (result) {
> dev_err(smu->adev->dev, "[%s] Failed to get activity monitor!", __func__);
> - return result;
> + goto out;
> }
> }
>
> @@ -1495,7 +1503,10 @@ do { \
> PRINT_DPM_MONITOR(Fclk_BoosterFreq);
> #undef PRINT_DPM_MONITOR
>
> - return size;
> + result = size;
> +out:
> + kfree(activity_monitor_external);
> + return result;
> }
>
> static int smu_v13_0_7_set_power_profile_mode(struct smu_context *smu, long *input, uint32_t size)

\
 
 \ /
  Last update: 2022-12-15 20:47    [W:0.088 / U:0.372 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site