From: Tianci Yin <[email protected]> [why] Since the variable fpu_recursion_depth is per-CPU type, it has one copy on each CPU, thread migration causes data consistency issue, then the call trace shows up. And preemption disabling can't prevent migration.
[how] Disable migration to ensure consistency of fpu_recursion_depth. Reviewed-by: Aurabindo Pillai <[email protected]> Signed-off-by: Tianci Yin <[email protected]> --- drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c b/drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c index 1743ca0a3641..c42aa947c969 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c @@ -89,6 +89,7 @@ void dc_fpu_begin(const char *function_name, const int line) if (*pcpu == 1) { #if defined(CONFIG_X86) + migrate_disable(); kernel_fpu_begin(); #elif defined(CONFIG_PPC64) if (cpu_has_feature(CPU_FTR_VSX_COMP)) { @@ -129,6 +130,7 @@ void dc_fpu_end(const char *function_name, const int line) if (*pcpu <= 0) { #if defined(CONFIG_X86) kernel_fpu_end(); + migrate_enable(); #elif defined(CONFIG_PPC64) if (cpu_has_feature(CPU_FTR_VSX_COMP)) { disable_kernel_vsx(); -- 2.34.1
