Christophe Leroy <christophe.le...@c-s.fr> writes: > On 06/03/2019 11:50 PM, Daniel Axtens wrote: >> Christophe Leroy <christophe.le...@c-s.fr> writes: >> >>> Hi, >>> >>> Ok, can you share your .config ? >> >> Sure! This one is with kasan off as the last build I did was testing to >> see if the code reorgisation was the cause of the issues. (it was not) >> >> >> >> >> This was the kasan-enabled config that failed to boot: >> >> > > Same issue with your .config under QEMU: > > A go with gdb shows: > > Breakpoint 3, 0xc000000000027b6c in exc_0x700_common () > => 0xc000000000027b6c <exc_0x700_common+0>: f8 01 00 70 std > r0,112(r1) > (gdb) bt > #0 0xc000000000027b6c in exc_0x700_common () > #1 0xc00000000136f80c in .udbg_init_memcons () >
Thanks for debugging this! > Without CONFIG_PPC_EARLY_DEBUG, it boots fine for me. Can you check on > your side ? Yes, that works on my side. > Deactivating KASAN for arch/powerpc/kernel/udbg.o and > arch/powerpc/sysdev/udbg_memcons.o is not enough, we hit a call to > strstr() in register_early_udbg_console(), and once we get rid of it (in > the same way as in prom_init.c) the next issue is register_console() and > I don't know what to do about that one. Disabling early debug seems like a reasonable restriction to add. I'll have a look at modules across this and book3s next. Regards, Daniel > > Christophe > >> >> >> Regards, >> Daniel >> >>> >>> Christophe >>> >>> Le 31/05/2019 à 03:29, Daniel Axtens a écrit : >>>> Hi Christophe, >>>> >>>> I tried this on the t4240rdb and it fails to boot if KASAN is >>>> enabled. It does boot with the patch applied but KASAN disabled, so that >>>> narrows it down a little bit. >>>> >>>> I need to focus on 3s first so I'll just drop 3e from my patch set for >>>> now. >>>> >>>> Regards, >>>> Daniel >>>> >>>>> The KASAN shadow area is mapped into vmemmap space: >>>>> 0x8000 0400 0000 0000 to 0x8000 0600 0000 0000. >>>>> For this vmemmap has to be disabled. >>>>> >>>>> Cc: Daniel Axtens <d...@axtens.net> >>>>> Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> >>>>> --- >>>>> arch/powerpc/Kconfig | 1 + >>>>> arch/powerpc/Kconfig.debug | 3 +- >>>>> arch/powerpc/include/asm/kasan.h | 11 +++ >>>>> arch/powerpc/kernel/Makefile | 2 + >>>>> arch/powerpc/kernel/head_64.S | 3 + >>>>> arch/powerpc/kernel/setup_64.c | 20 +++--- >>>>> arch/powerpc/mm/kasan/Makefile | 1 + >>>>> arch/powerpc/mm/kasan/kasan_init_64.c | 129 >>>>> ++++++++++++++++++++++++++++++++++ >>>>> 8 files changed, 159 insertions(+), 11 deletions(-) >>>>> create mode 100644 arch/powerpc/mm/kasan/kasan_init_64.c >>>>> >>>>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig >>>>> index 1a2fb50126b2..e0b7c45e4dc7 100644 >>>>> --- a/arch/powerpc/Kconfig >>>>> +++ b/arch/powerpc/Kconfig >>>>> @@ -174,6 +174,7 @@ config PPC >>>>> select HAVE_ARCH_AUDITSYSCALL >>>>> select HAVE_ARCH_JUMP_LABEL >>>>> select HAVE_ARCH_KASAN if PPC32 >>>>> + select HAVE_ARCH_KASAN if PPC_BOOK3E_64 && >>>>> !SPARSEMEM_VMEMMAP >>>>> select HAVE_ARCH_KGDB >>>>> select HAVE_ARCH_MMAP_RND_BITS >>>>> select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT >>>>> diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug >>>>> index 61febbbdd02b..b4140dd6b4e4 100644 >>>>> --- a/arch/powerpc/Kconfig.debug >>>>> +++ b/arch/powerpc/Kconfig.debug >>>>> @@ -370,4 +370,5 @@ config PPC_FAST_ENDIAN_SWITCH >>>>> config KASAN_SHADOW_OFFSET >>>>> hex >>>>> depends on KASAN >>>>> - default 0xe0000000 >>>>> + default 0xe0000000 if PPC32 >>>>> + default 0x6800040000000000 if PPC64 >>>>> diff --git a/arch/powerpc/include/asm/kasan.h >>>>> b/arch/powerpc/include/asm/kasan.h >>>>> index 296e51c2f066..756b3d58f921 100644 >>>>> --- a/arch/powerpc/include/asm/kasan.h >>>>> +++ b/arch/powerpc/include/asm/kasan.h >>>>> @@ -23,10 +23,21 @@ >>>>> >>>>> #define KASAN_SHADOW_OFFSET ASM_CONST(CONFIG_KASAN_SHADOW_OFFSET) >>>>> >>>>> +#ifdef CONFIG_PPC32 >>>>> #define KASAN_SHADOW_END 0UL >>>>> >>>>> #define KASAN_SHADOW_SIZE (KASAN_SHADOW_END - KASAN_SHADOW_START) >>>>> >>>>> +#else >>>>> + >>>>> +#include <asm/pgtable.h> >>>>> + >>>>> +#define KASAN_SHADOW_SIZE (KERN_VIRT_SIZE >> >>>>> KASAN_SHADOW_SCALE_SHIFT) >>>>> + >>>>> +#define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE) >>>>> + >>>>> +#endif /* CONFIG_PPC32 */ >>>>> + >>>>> #ifdef CONFIG_KASAN >>>>> void kasan_early_init(void); >>>>> void kasan_mmu_init(void); >>>>> diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile >>>>> index 0ea6c4aa3a20..7f232c06f11d 100644 >>>>> --- a/arch/powerpc/kernel/Makefile >>>>> +++ b/arch/powerpc/kernel/Makefile >>>>> @@ -35,6 +35,8 @@ KASAN_SANITIZE_early_32.o := n >>>>> KASAN_SANITIZE_cputable.o := n >>>>> KASAN_SANITIZE_prom_init.o := n >>>>> KASAN_SANITIZE_btext.o := n >>>>> +KASAN_SANITIZE_paca.o := n >>>>> +KASAN_SANITIZE_setup_64.o := n >>>>> >>>>> ifdef CONFIG_KASAN >>>>> CFLAGS_early_32.o += -DDISABLE_BRANCH_PROFILING >>>>> diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S >>>>> index 3fad8d499767..80fbd8024fb2 100644 >>>>> --- a/arch/powerpc/kernel/head_64.S >>>>> +++ b/arch/powerpc/kernel/head_64.S >>>>> @@ -966,6 +966,9 @@ start_here_multiplatform: >>>>> * and SLB setup before we turn on relocation. >>>>> */ >>>>> >>>>> +#ifdef CONFIG_KASAN >>>>> + bl kasan_early_init >>>>> +#endif >>>>> /* Restore parameters passed from prom_init/kexec */ >>>>> mr r3,r31 >>>>> bl early_setup /* also sets r13 and SPRG_PACA >>>>> */ >>>>> diff --git a/arch/powerpc/kernel/setup_64.c >>>>> b/arch/powerpc/kernel/setup_64.c >>>>> index ba404dd9ce1d..d2bf860dd966 100644 >>>>> --- a/arch/powerpc/kernel/setup_64.c >>>>> +++ b/arch/powerpc/kernel/setup_64.c >>>>> @@ -311,6 +311,16 @@ void __init early_setup(unsigned long dt_ptr) >>>>> DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr); >>>>> >>>>> /* >>>>> + * Configure exception handlers. This include setting up trampolines >>>>> + * if needed, setting exception endian mode, etc... >>>>> + */ >>>>> + configure_exceptions(); >>>>> + >>>>> + /* Apply all the dynamic patching */ >>>>> + apply_feature_fixups(); >>>>> + setup_feature_keys(); >>>>> + >>>>> + /* >>>>> * Do early initialization using the flattened device >>>>> * tree, such as retrieving the physical memory map or >>>>> * calculating/retrieving the hash table size. >>>>> @@ -325,16 +335,6 @@ void __init early_setup(unsigned long dt_ptr) >>>>> setup_paca(paca_ptrs[boot_cpuid]); >>>>> fixup_boot_paca(); >>>>> >>>>> - /* >>>>> - * Configure exception handlers. This include setting up trampolines >>>>> - * if needed, setting exception endian mode, etc... >>>>> - */ >>>>> - configure_exceptions(); >>>>> - >>>>> - /* Apply all the dynamic patching */ >>>>> - apply_feature_fixups(); >>>>> - setup_feature_keys(); >>>>> - >>>>> /* Initialize the hash table or TLB handling */ >>>>> early_init_mmu(); >>>>> >>>>> diff --git a/arch/powerpc/mm/kasan/Makefile >>>>> b/arch/powerpc/mm/kasan/Makefile >>>>> index 6577897673dd..0bfbe3892808 100644 >>>>> --- a/arch/powerpc/mm/kasan/Makefile >>>>> +++ b/arch/powerpc/mm/kasan/Makefile >>>>> @@ -3,3 +3,4 @@ >>>>> KASAN_SANITIZE := n >>>>> >>>>> obj-$(CONFIG_PPC32) += kasan_init_32.o >>>>> +obj-$(CONFIG_PPC64) += kasan_init_64.o >>>>> diff --git a/arch/powerpc/mm/kasan/kasan_init_64.c >>>>> b/arch/powerpc/mm/kasan/kasan_init_64.c >>>>> new file mode 100644 >>>>> index 000000000000..7fd71b8e883b >>>>> --- /dev/null >>>>> +++ b/arch/powerpc/mm/kasan/kasan_init_64.c >>>>> @@ -0,0 +1,129 @@ >>>>> +// SPDX-License-Identifier: GPL-2.0 >>>>> + >>>>> +#define DISABLE_BRANCH_PROFILING >>>>> + >>>>> +#include <linux/kasan.h> >>>>> +#include <linux/printk.h> >>>>> +#include <linux/memblock.h> >>>>> +#include <linux/sched/task.h> >>>>> +#include <asm/pgalloc.h> >>>>> + >>>>> +static void __init kasan_populate_pte(pte_t *ptep, pgprot_t prot) >>>>> +{ >>>>> + unsigned long va = (unsigned long)kasan_early_shadow_page; >>>>> + phys_addr_t pa = __pa(kasan_early_shadow_page); >>>>> + int i; >>>>> + >>>>> + for (i = 0; i < PTRS_PER_PTE; i++, ptep++) >>>>> + __set_pte_at(&init_mm, va, ptep, pfn_pte(PHYS_PFN(pa), prot), >>>>> 0); >>>>> +} >>>>> + >>>>> +static void __init kasan_populate_pmd(pmd_t *pmdp) >>>>> +{ >>>>> + int i; >>>>> + >>>>> + for (i = 0; i < PTRS_PER_PMD; i++) >>>>> + pmd_populate_kernel(&init_mm, pmdp + i, kasan_early_shadow_pte); >>>>> +} >>>>> + >>>>> +static void __init kasan_populate_pud(pud_t *pudp) >>>>> +{ >>>>> + int i; >>>>> + >>>>> + for (i = 0; i < PTRS_PER_PUD; i++) >>>>> + pud_populate(&init_mm, pudp + i, kasan_early_shadow_pmd); >>>>> +} >>>>> + >>>>> +static void __init *kasan_alloc_pgtable(unsigned long size) >>>>> +{ >>>>> + void *ptr = memblock_alloc_try_nid(size, size, MEMBLOCK_LOW_LIMIT, >>>>> + __pa(MAX_DMA_ADDRESS), NUMA_NO_NODE); >>>>> + >>>>> + if (!ptr) >>>>> + panic("%s: Failed to allocate %lu bytes align=0x%lx >>>>> max_addr=%lx\n", >>>>> + __func__, size, size, __pa(MAX_DMA_ADDRESS)); >>>>> + >>>>> + return ptr; >>>>> +} >>>>> + >>>>> +static int __init kasan_map_page(unsigned long va, unsigned long pa, >>>>> pgprot_t prot) >>>>> +{ >>>>> + pgd_t *pgdp = pgd_offset_k(va); >>>>> + pud_t *pudp; >>>>> + pmd_t *pmdp; >>>>> + pte_t *ptep; >>>>> + >>>>> + if (pgd_none(*pgdp) || (void *)pgd_page_vaddr(*pgdp) == >>>>> kasan_early_shadow_pud) { >>>>> + pudp = kasan_alloc_pgtable(PUD_TABLE_SIZE); >>>>> + kasan_populate_pud(pudp); >>>>> + pgd_populate(&init_mm, pgdp, pudp); >>>>> + } >>>>> + pudp = pud_offset(pgdp, va); >>>>> + if (pud_none(*pudp) || (void *)pud_page_vaddr(*pudp) == >>>>> kasan_early_shadow_pmd) { >>>>> + pmdp = kasan_alloc_pgtable(PMD_TABLE_SIZE); >>>>> + kasan_populate_pmd(pmdp); >>>>> + pud_populate(&init_mm, pudp, pmdp); >>>>> + } >>>>> + pmdp = pmd_offset(pudp, va); >>>>> + if (!pmd_present(*pmdp) || (void *)pmd_page_vaddr(*pmdp) == >>>>> kasan_early_shadow_pte) { >>>>> + ptep = kasan_alloc_pgtable(PTE_TABLE_SIZE); >>>>> + kasan_populate_pte(ptep, PAGE_KERNEL); >>>>> + pmd_populate_kernel(&init_mm, pmdp, ptep); >>>>> + } >>>>> + ptep = pte_offset_kernel(pmdp, va); >>>>> + >>>>> + __set_pte_at(&init_mm, va, ptep, pfn_pte(pa >> PAGE_SHIFT, prot), 0); >>>>> + >>>>> + return 0; >>>>> +} >>>>> + >>>>> +static void __init kasan_init_region(struct memblock_region *reg) >>>>> +{ >>>>> + void *start = __va(reg->base); >>>>> + void *end = __va(reg->base + reg->size); >>>>> + unsigned long k_start, k_end, k_cur; >>>>> + >>>>> + if (start >= end) >>>>> + return; >>>>> + >>>>> + k_start = (unsigned long)kasan_mem_to_shadow(start); >>>>> + k_end = (unsigned long)kasan_mem_to_shadow(end); >>>>> + >>>>> + for (k_cur = k_start; k_cur < k_end; k_cur += PAGE_SIZE) { >>>>> + void *va = memblock_alloc(PAGE_SIZE, PAGE_SIZE); >>>>> + >>>>> + kasan_map_page(k_cur, __pa(va), PAGE_KERNEL); >>>>> + } >>>>> + flush_tlb_kernel_range(k_start, k_end); >>>>> +} >>>>> + >>>>> +void __init kasan_init(void) >>>>> +{ >>>>> + struct memblock_region *reg; >>>>> + >>>>> + for_each_memblock(memory, reg) >>>>> + kasan_init_region(reg); >>>>> + >>>>> + /* It's too early to use clear_page() ! */ >>>>> + memset(kasan_early_shadow_page, 0, sizeof(kasan_early_shadow_page)); >>>>> + >>>>> + /* Enable error messages */ >>>>> + init_task.kasan_depth = 0; >>>>> + pr_info("KASAN init done\n"); >>>>> +} >>>>> + >>>>> +/* The early shadow maps everything to a single page of zeroes */ >>>>> +asmlinkage void __init kasan_early_init(void) >>>>> +{ >>>>> + unsigned long addr = KASAN_SHADOW_START; >>>>> + unsigned long end = KASAN_SHADOW_END; >>>>> + pgd_t *pgdp = pgd_offset_k(addr); >>>>> + >>>>> + kasan_populate_pte(kasan_early_shadow_pte, PAGE_KERNEL); >>>>> + kasan_populate_pmd(kasan_early_shadow_pmd); >>>>> + kasan_populate_pud(kasan_early_shadow_pud); >>>>> + >>>>> + do { >>>>> + pgd_populate(&init_mm, pgdp, kasan_early_shadow_pud); >>>>> + } while (pgdp++, addr = pgd_addr_end(addr, end), addr != end); >>>>> +} >>>>> -- >>>>> 2.13.3