On 10/11/2017 01:22 AM, Abbott Liu wrote: > From: Andrey Ryabinin <a.ryabi...@samsung.com> > > This patch initializes KASan shadow region's page table and memory. > There are two stage for KASan initializing: > 1. At early boot stage the whole shadow region is mapped to just > one physical page (kasan_zero_page). It's finished by the function > kasan_early_init which is called by __mmap_switched(arch/arm/kernel/ > head-common.S) > > 2. After the calling of paging_init, we use kasan_zero_page as zero > shadow for some memory that KASan don't need to track, and we alloc > new shadow space for the other memory that KASan need to track. These > issues are finished by the function kasan_init which is call by setup_arch. > > Cc: Andrey Ryabinin <a.ryabi...@samsung.com> > Signed-off-by: Abbott Liu <liuwenli...@huawei.com> > ---
[snip] \ > @@ -140,6 +149,30 @@ extern void cpu_resume(void); > pg &= ~0x3fff; \ > (pgd_t *)phys_to_virt(pg); \ > }) > + > +#define cpu_set_ttbr(nr, val) \ > + do { \ > + u64 ttbr = val; \ > + __asm__("mcr p15, 0, %0, c2, c0, 0" \ > + : : "r" (ttbr)); \ > + } while (0) nr seems to be unused here? > + > +#define cpu_get_ttbr(nr) \ > + ({ \ > + unsigned long ttbr; \ > + __asm__("mrc p15, 0, %0, c2, c0, 0" \ > + : "=r" (ttbr)); \ > + ttbr; \ > + }) > + > +#define cpu_set_ttbr0(val) \ > + do { \ > + u64 ttbr = val; \ > + __asm__("mcr p15, 0, %0, c2, c0, 0" \ > + : : "r" (ttbr)); \ > + } while (0) > + Why is not cpu_set_ttbr0() not using cpu_set_ttbr()? > + > #endif > > #else /*!CONFIG_MMU */ > diff --git a/arch/arm/include/asm/thread_info.h > b/arch/arm/include/asm/thread_info.h > index 1d468b5..52c4858 100644 > --- a/arch/arm/include/asm/thread_info.h > +++ b/arch/arm/include/asm/thread_info.h > @@ -16,7 +16,11 @@ > #include <asm/fpstate.h> > #include <asm/page.h> > > +#ifdef CONFIG_KASAN > +#define THREAD_SIZE_ORDER 2 > +#else > #define THREAD_SIZE_ORDER 1 > +#endif > #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER) > #define THREAD_START_SP (THREAD_SIZE - 8) > > diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S > index 8733012..c17f4a2 100644 > --- a/arch/arm/kernel/head-common.S > +++ b/arch/arm/kernel/head-common.S > @@ -101,7 +101,11 @@ __mmap_switched: > str r2, [r6] @ Save atags pointer > cmp r7, #0 > strne r0, [r7] @ Save control register values > +#ifdef CONFIG_KASAN > + b kasan_early_init > +#else > b start_kernel > +#endif Please don't make this "exclusive" just conditionally call kasan_early_init(), remove the call to start_kernel from kasan_early_init and keep the call to start_kernel here. > ENDPROC(__mmap_switched) > > .align 2 [snip] > +void __init kasan_early_init(void) > +{ > + struct proc_info_list *list; > + > + /* > + * locate processor in the list of supported processor > + * types. The linker builds this table for us from the > + * entries in arch/arm/mm/proc-*.S > + */ > + list = lookup_processor_type(read_cpuid_id()); > + if (list) { > +#ifdef MULTI_CPU > + processor = *list->proc; > +#endif > + } I could not quite spot in your patch series when do you need this information? -- Florian