This patch declares percpu variables in __seg_gs/__seg_fs named AS and keeps them named AS qualified until they are dereferenced with percpu accessor. This approach enables various compiler check for cross-namespace variable assignments. Signed-off-by: Uros Bizjak <ubizjak@xxxxxxxxx> Cc: Dennis Zhou <dennis@xxxxxxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx> Cc: Nadav Amit <nadav.amit@xxxxxxxxx> Cc: Brian Gerst <brgerst@xxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> --- arch/x86/include/asm/percpu.h | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h index 27f668660abe..61b875243ea3 100644 --- a/arch/x86/include/asm/percpu.h +++ b/arch/x86/include/asm/percpu.h @@ -95,9 +95,19 @@ #endif /* CONFIG_SMP */ -#define __my_cpu_type(var) typeof(var) __percpu_seg_override -#define __my_cpu_ptr(ptr) (__my_cpu_type(*(ptr))*)(__force uintptr_t)(ptr) -#define __my_cpu_var(var) (*__my_cpu_ptr(&(var))) +#if defined(CONFIG_USE_X86_SEG_SUPPORT) && \ + defined(CONFIG_CC_HAS_TYPEOF_UNQUAL) && !defined(__CHECKER__) +# define __my_cpu_type(var) typeof(var) +# define __my_cpu_ptr(ptr) (ptr) +# define __my_cpu_var(var) (var) + +# define __per_cpu_qual __percpu_seg_override +#else +# define __my_cpu_type(var) typeof(var) __percpu_seg_override +# define __my_cpu_ptr(ptr) (__my_cpu_type(*(ptr))*)(__force uintptr_t)(ptr) +# define __my_cpu_var(var) (*__my_cpu_ptr(&(var))) +#endif + #define __percpu_arg(x) __percpu_prefix "%" #x #define __force_percpu_arg(x) __force_percpu_prefix "%" #x -- 2.42.0
