From 334b2cea811944df99ae2172bcc0effcdfdbe862 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 28 Sep 2022 09:30:31 +0200 Subject: [PATCH] x86/mm: Add prot_sethuge() helper to abstract out _PAGE_PSE handling We still have some historic cases of direct fiddling of page attributes with (dangerous & fragile) type casting and address shifting. Add the prot_sethuge() helper instead that gets the types right and doesn't have to transform addresses. ( Also add a debug check to make sure this doesn't get applied to _PAGE_BIT_PAT/_PAGE_BIT_PAT_LARGE pages. ) Signed-off-by: Linus Torvalds Signed-off-by: Ingo Molnar Reviewed-by: Dave Hansen --- arch/x86/mm/init_64.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 0fe690e..7ea7d47 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -90,6 +90,12 @@ DEFINE_ENTRY(pud, pud, init) DEFINE_ENTRY(pmd, pmd, init) DEFINE_ENTRY(pte, pte, init) +static inline pgprot_t prot_sethuge(pgprot_t prot) +{ + WARN_ON_ONCE(pgprot_val(prot) & _PAGE_PAT); + + return __pgprot(pgprot_val(prot) | _PAGE_PSE); +} /* * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the @@ -557,9 +563,8 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end, if (page_size_mask & (1<> PAGE_SHIFT, - __pgprot(pgprot_val(prot) | _PAGE_PSE)), + set_pmd_init(pmd, + pfn_pmd(paddr >> PAGE_SHIFT, prot_sethuge(prot)), init); spin_unlock(&init_mm.page_table_lock); paddr_last = paddr_next; @@ -644,12 +649,8 @@ phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end, if (page_size_mask & (1<> PAGE_SHIFT, - prot), + set_pud_init(pud, + pfn_pud(paddr >> PAGE_SHIFT, prot_sethuge(prot)), init); spin_unlock(&init_mm.page_table_lock); paddr_last = paddr_next; -- 2.7.4