From 2dece445b6dbdaa3d94f38ef44aa1b63bc2a6bb9 Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Tue, 10 Jan 2017 13:35:41 -0800 Subject: mm/cma: Cleanup highmem check 6b101e2a3ce4 ("mm/CMA: fix boot regression due to physical address of high_memory") added checks to use __pa_nodebug on x86 since CONFIG_DEBUG_VIRTUAL complains about high_memory not being linearlly mapped. arm64 is now getting support for CONFIG_DEBUG_VIRTUAL as well. Rather than add an explosion of arches to the #ifdef, switch to an alternate method to calculate the physical start of highmem using the page before highmem starts. This avoids the need for the #ifdef and extra __pa_nodebug calls. Reviewed-by: Mark Rutland Tested-by: Mark Rutland Signed-off-by: Laura Abbott Signed-off-by: Will Deacon --- mm/cma.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) (limited to 'mm') diff --git a/mm/cma.c b/mm/cma.c index c960459eda7e..94b3460cd608 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -235,18 +235,13 @@ int __init cma_declare_contiguous(phys_addr_t base, phys_addr_t highmem_start; int ret = 0; -#ifdef CONFIG_X86 /* - * high_memory isn't direct mapped memory so retrieving its physical - * address isn't appropriate. But it would be useful to check the - * physical address of the highmem boundary so it's justifiable to get - * the physical address from it. On x86 there is a validation check for - * this case, so the following workaround is needed to avoid it. + * We can't use __pa(high_memory) directly, since high_memory + * isn't a valid direct map VA, and DEBUG_VIRTUAL will (validly) + * complain. Find the boundary by adding one to the last valid + * address. */ - highmem_start = __pa_nodebug(high_memory); -#else - highmem_start = __pa(high_memory); -#endif + highmem_start = __pa(high_memory - 1) + 1; pr_debug("%s(size %pa, base %pa, limit %pa alignment %pa)\n", __func__, &size, &base, &limit, &alignment); -- cgit v1.2.3 From 5c6a84a3f4558a6115fef1b59343c7ae56b3abc3 Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Tue, 10 Jan 2017 13:35:44 -0800 Subject: mm/kasan: Switch to using __pa_symbol and lm_alias __pa_symbol is the correct API to find the physical address of symbols. Switch to it to allow for debugging APIs to work correctly. Other functions such as p*d_populate may call __pa internally. Ensure that the address passed is in the linear region by calling lm_alias. Reviewed-by: Mark Rutland Tested-by: Mark Rutland Signed-off-by: Laura Abbott Signed-off-by: Will Deacon --- mm/kasan/kasan_init.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'mm') diff --git a/mm/kasan/kasan_init.c b/mm/kasan/kasan_init.c index 3f9a41cf0ac6..31238dad85fb 100644 --- a/mm/kasan/kasan_init.c +++ b/mm/kasan/kasan_init.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include @@ -49,7 +50,7 @@ static void __init zero_pte_populate(pmd_t *pmd, unsigned long addr, pte_t *pte = pte_offset_kernel(pmd, addr); pte_t zero_pte; - zero_pte = pfn_pte(PFN_DOWN(__pa(kasan_zero_page)), PAGE_KERNEL); + zero_pte = pfn_pte(PFN_DOWN(__pa_symbol(kasan_zero_page)), PAGE_KERNEL); zero_pte = pte_wrprotect(zero_pte); while (addr + PAGE_SIZE <= end) { @@ -69,7 +70,7 @@ static void __init zero_pmd_populate(pud_t *pud, unsigned long addr, next = pmd_addr_end(addr, end); if (IS_ALIGNED(addr, PMD_SIZE) && end - addr >= PMD_SIZE) { - pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte); + pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte)); continue; } @@ -92,9 +93,9 @@ static void __init zero_pud_populate(pgd_t *pgd, unsigned long addr, if (IS_ALIGNED(addr, PUD_SIZE) && end - addr >= PUD_SIZE) { pmd_t *pmd; - pud_populate(&init_mm, pud, kasan_zero_pmd); + pud_populate(&init_mm, pud, lm_alias(kasan_zero_pmd)); pmd = pmd_offset(pud, addr); - pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte); + pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte)); continue; } @@ -135,11 +136,11 @@ void __init kasan_populate_zero_shadow(const void *shadow_start, * puds,pmds, so pgd_populate(), pud_populate() * is noops. */ - pgd_populate(&init_mm, pgd, kasan_zero_pud); + pgd_populate(&init_mm, pgd, lm_alias(kasan_zero_pud)); pud = pud_offset(pgd, addr); - pud_populate(&init_mm, pud, kasan_zero_pmd); + pud_populate(&init_mm, pud, lm_alias(kasan_zero_pmd)); pmd = pmd_offset(pud, addr); - pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte); + pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte)); continue; } -- cgit v1.2.3 From 46f6236aa1c48e06b10a2fe0386ac4114b438622 Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Tue, 10 Jan 2017 13:35:45 -0800 Subject: mm/usercopy: Switch to using lm_alias The usercopy checking code currently calls __va(__pa(...)) to check for aliases on symbols. Switch to using lm_alias instead. Reviewed-by: Mark Rutland Tested-by: Mark Rutland Acked-by: Kees Cook Signed-off-by: Laura Abbott Signed-off-by: Will Deacon --- mm/usercopy.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'mm') diff --git a/mm/usercopy.c b/mm/usercopy.c index 3c8da0af9695..8345299e3e3b 100644 --- a/mm/usercopy.c +++ b/mm/usercopy.c @@ -108,13 +108,13 @@ static inline const char *check_kernel_text_object(const void *ptr, * __pa() is not just the reverse of __va(). This can be detected * and checked: */ - textlow_linear = (unsigned long)__va(__pa(textlow)); + textlow_linear = (unsigned long)lm_alias(textlow); /* No different mapping: we're done. */ if (textlow_linear == textlow) return NULL; /* Check the secondary mapping... */ - texthigh_linear = (unsigned long)__va(__pa(texthigh)); + texthigh_linear = (unsigned long)lm_alias(texthigh); if (overlaps(ptr, n, textlow_linear, texthigh_linear)) return ""; -- cgit v1.2.3