From: Andrey Ryabinin Date: Wed, 10 Jan 2018 15:36:02 +0000 (+0300) Subject: x86/kasan: Panic if there is not enough memory to boot X-Git-Tag: v4.14.15~60 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=fbb8c0acc8e1458acdae392a5226b371243444e4;p=platform%2Fkernel%2Flinux-exynos.git x86/kasan: Panic if there is not enough memory to boot commit 0d39e2669d7b0fefd2d8f9e7868ae669b364d9ba upstream. Currently KASAN doesn't panic in case it don't have enough memory to boot. Instead, it crashes in some random place: kernel BUG at arch/x86/mm/physaddr.c:27! RIP: 0010:__phys_addr+0x268/0x276 Call Trace: kasan_populate_shadow+0x3f2/0x497 kasan_init+0x12e/0x2b2 setup_arch+0x2825/0x2a2c start_kernel+0xc8/0x15f4 x86_64_start_reservations+0x2a/0x2c x86_64_start_kernel+0x72/0x75 secondary_startup_64+0xa5/0xb0 Use memblock_virt_alloc_try_nid() for allocations without failure fallback. It will panic with an out of memory message. Reported-by: kernel test robot Signed-off-by: Andrey Ryabinin Signed-off-by: Thomas Gleixner Acked-by: Dmitry Vyukov Cc: kasan-dev@googlegroups.com Cc: Alexander Potapenko Cc: lkp@01.org Link: https://lkml.kernel.org/r/20180110153602.18919-1-aryabinin@virtuozzo.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/mm/kasan_init_64.c b/arch/x86/mm/kasan_init_64.c index 47388f0..af6f2f9 100644 --- a/arch/x86/mm/kasan_init_64.c +++ b/arch/x86/mm/kasan_init_64.c @@ -21,10 +21,14 @@ extern struct range pfn_mapped[E820_MAX_ENTRIES]; static p4d_t tmp_p4d_table[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE); -static __init void *early_alloc(size_t size, int nid) +static __init void *early_alloc(size_t size, int nid, bool panic) { - return memblock_virt_alloc_try_nid_nopanic(size, size, - __pa(MAX_DMA_ADDRESS), BOOTMEM_ALLOC_ACCESSIBLE, nid); + if (panic) + return memblock_virt_alloc_try_nid(size, size, + __pa(MAX_DMA_ADDRESS), BOOTMEM_ALLOC_ACCESSIBLE, nid); + else + return memblock_virt_alloc_try_nid_nopanic(size, size, + __pa(MAX_DMA_ADDRESS), BOOTMEM_ALLOC_ACCESSIBLE, nid); } static void __init kasan_populate_pmd(pmd_t *pmd, unsigned long addr, @@ -38,14 +42,14 @@ static void __init kasan_populate_pmd(pmd_t *pmd, unsigned long addr, if (boot_cpu_has(X86_FEATURE_PSE) && ((end - addr) == PMD_SIZE) && IS_ALIGNED(addr, PMD_SIZE)) { - p = early_alloc(PMD_SIZE, nid); + p = early_alloc(PMD_SIZE, nid, false); if (p && pmd_set_huge(pmd, __pa(p), PAGE_KERNEL)) return; else if (p) memblock_free(__pa(p), PMD_SIZE); } - p = early_alloc(PAGE_SIZE, nid); + p = early_alloc(PAGE_SIZE, nid, true); pmd_populate_kernel(&init_mm, pmd, p); } @@ -57,7 +61,7 @@ static void __init kasan_populate_pmd(pmd_t *pmd, unsigned long addr, if (!pte_none(*pte)) continue; - p = early_alloc(PAGE_SIZE, nid); + p = early_alloc(PAGE_SIZE, nid, true); entry = pfn_pte(PFN_DOWN(__pa(p)), PAGE_KERNEL); set_pte_at(&init_mm, addr, pte, entry); } while (pte++, addr += PAGE_SIZE, addr != end); @@ -75,14 +79,14 @@ static void __init kasan_populate_pud(pud_t *pud, unsigned long addr, if (boot_cpu_has(X86_FEATURE_GBPAGES) && ((end - addr) == PUD_SIZE) && IS_ALIGNED(addr, PUD_SIZE)) { - p = early_alloc(PUD_SIZE, nid); + p = early_alloc(PUD_SIZE, nid, false); if (p && pud_set_huge(pud, __pa(p), PAGE_KERNEL)) return; else if (p) memblock_free(__pa(p), PUD_SIZE); } - p = early_alloc(PAGE_SIZE, nid); + p = early_alloc(PAGE_SIZE, nid, true); pud_populate(&init_mm, pud, p); } @@ -101,7 +105,7 @@ static void __init kasan_populate_p4d(p4d_t *p4d, unsigned long addr, unsigned long next; if (p4d_none(*p4d)) { - void *p = early_alloc(PAGE_SIZE, nid); + void *p = early_alloc(PAGE_SIZE, nid, true); p4d_populate(&init_mm, p4d, p); } @@ -122,7 +126,7 @@ static void __init kasan_populate_pgd(pgd_t *pgd, unsigned long addr, unsigned long next; if (pgd_none(*pgd)) { - p = early_alloc(PAGE_SIZE, nid); + p = early_alloc(PAGE_SIZE, nid, true); pgd_populate(&init_mm, pgd, p); }