On 03.06.2015 11:44, Andrey Ryabinin wrote: > On 06/03/2015 10:44 AM, Ingo Molnar wrote: >> >> * Alexander Popov <[email protected]> wrote: >> >>> #ifdef CONFIG_KASAN >>> void __init kasan_map_early_shadow(pgd_t *pgd); >>> +void __init kasan_early_init(void); >>> void __init kasan_init(void); >>> #else >>> static inline void kasan_map_early_shadow(pgd_t *pgd) { } >>> +static inline void kasan_early_init(void) { } >>> static inline void kasan_init(void) { } >>> #endif >>> >>> diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c >>> index 2b55ee6..e9a84a1 100644 >>> --- a/arch/x86/kernel/head64.c >>> +++ b/arch/x86/kernel/head64.c >>> @@ -161,11 +161,15 @@ asmlinkage __visible void __init >>> x86_64_start_kernel(char * real_mode_data) >>> /* Kill off the identity-map trampoline */ >>> reset_early_page_tables(); >>> >>> - kasan_map_early_shadow(early_level4_pgt); >>> - >>> - /* clear bss before set_intr_gate with early_idt_handler */ >>> + /* >>> + * Clear bss before kasan_early_init and set_intr_gate >>> + * with early_idt_handler >>> + */ >>> clear_bss(); >>> >>> + kasan_early_init(); >>> + kasan_map_early_shadow(early_level4_pgt); >> >> So why isn't kasan_map_early_shadow() called in kasan_early_init()? >> >> High level x86 init code should not be polluted with too many low level >> details. >> > > Agreed. Eventually, with the patch bellow, we could get rid of the second > kasan_map_early_shadow(init_level4_pgt) call in x86_64_start_kernel(). > Make it static, and call it from kasan_early_init() only. > > ------------------------------------------------------ > From: Andrey Ryabinin <[email protected]> > Subject: [PATCH] x86_64: remove not needed clear_page for init_level4_page > > Commit 8170e6bed465 ("x86, 64bit: Use a #PF handler to materialize > early mappings on demand") introduced clear_page(init_level4_pgt); > call in x86_64_start_kernel(). However, this clear_page is useless > because init_level4_page already filled with zeroes in head_64.S > > Commit message in 8170e6bed465 says that this clear_page() was > dropped in v7, but it accidentally reappeared in later versions > of that patchset. > > Signed-off-by: Andrey Ryabinin <[email protected]> > --- > arch/x86/kernel/head64.c | 1 - > 1 file changed, 1 deletion(-) > > diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c > index 5a46681..6a6eefd 100644 > --- a/arch/x86/kernel/head64.c > +++ b/arch/x86/kernel/head64.c > @@ -177,7 +177,6 @@ asmlinkage __visible void __init x86_64_start_kernel(char > * real_mode_data) > */ > load_ucode_bsp(); > > - clear_page(init_level4_pgt); > /* set init_level4_pgt kernel high mapping*/ > init_level4_pgt[511] = early_level4_pgt[511]; >
Hello Ingo and Andrey. Should I make a "patch series" containing Andrey's patch and the 5'th version of my patch or just include changes from Andrey's patch into mine? Best regards, Alexander -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
