From: Steven Price steven.price@arm.com
mainline inclusion from mainline-v5.6-rc1 commit 8aa82df3c123129025a364d8f823929cc488b834 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I4EUVI CVE: NA
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walk_page_range() is going to be allowed to walk page tables other than those of user space. For this it needs to know when it has reached a 'leaf' entry in the page tables. This information will be provided by the p?d_leaf() functions/macros.
For arm64, we already have p?d_sect() macros which we can reuse for p?d_leaf().
pud_sect() is defined as a dummy function when CONFIG_PGTABLE_LEVELS < 3 or CONFIG_ARM64_64K_PAGES is defined. However when the kernel is configured this way then architecturally it isn't allowed to have a large page at this level, and any code using these page walking macros is implicitly relying on the page size/number of levels being the same as the kernel. So it is safe to reuse this for p?d_leaf() as it is an architectural restriction.
Link: http://lkml.kernel.org/r/20191218162402.45610-5-steven.price@arm.com Signed-off-by: Steven Price steven.price@arm.com Acked-by: Catalin Marinas catalin.marinas@arm.com Cc: Catalin Marinas catalin.marinas@arm.com Cc: Will Deacon will@kernel.org Cc: Albert Ou aou@eecs.berkeley.edu Cc: Alexandre Ghiti alex@ghiti.fr Cc: Andy Lutomirski luto@kernel.org Cc: Ard Biesheuvel ard.biesheuvel@linaro.org Cc: Arnd Bergmann arnd@arndb.de Cc: Benjamin Herrenschmidt benh@kernel.crashing.org Cc: Borislav Petkov bp@alien8.de Cc: Christian Borntraeger borntraeger@de.ibm.com Cc: Dave Hansen dave.hansen@linux.intel.com Cc: David S. Miller davem@davemloft.net Cc: Heiko Carstens heiko.carstens@de.ibm.com Cc: "H. Peter Anvin" hpa@zytor.com Cc: Ingo Molnar mingo@redhat.com Cc: James Hogan jhogan@kernel.org Cc: James Morse james.morse@arm.com Cc: Jerome Glisse jglisse@redhat.com Cc: "Liang, Kan" kan.liang@linux.intel.com Cc: Mark Rutland mark.rutland@arm.com Cc: Michael Ellerman mpe@ellerman.id.au Cc: Paul Burton paul.burton@mips.com Cc: Paul Mackerras paulus@samba.org Cc: Paul Walmsley paul.walmsley@sifive.com Cc: Peter Zijlstra peterz@infradead.org Cc: Ralf Baechle ralf@linux-mips.org Cc: Russell King linux@armlinux.org.uk Cc: Thomas Gleixner tglx@linutronix.de Cc: Vasily Gorbik gor@linux.ibm.com Cc: Vineet Gupta vgupta@synopsys.com Cc: Zong Li zong.li@sifive.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Rui Xiang rui.xiang@huawei.com Reviewed-by: Ding Tianhong dingtianhong@huawei.com Reviewed-by: Zefan Li lizefan@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- arch/arm64/include/asm/pgtable.h | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 85af92cb24560..f4abd58262403 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -417,6 +417,7 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, PMD_TYPE_TABLE) #define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \ PMD_TYPE_SECT) +#define pmd_leaf(pmd) pmd_sect(pmd)
#if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3 static inline bool pud_sect(pud_t pud) { return false; } @@ -482,6 +483,7 @@ static inline void pte_unmap(pte_t *pte) { } #define pud_none(pud) (!pud_val(pud)) #define pud_bad(pud) (!(pud_val(pud) & PUD_TABLE_BIT)) #define pud_present(pud) pte_present(pud_pte(pud)) +#define pud_leaf(pud) pud_sect(pud) #define pud_valid(pud) pte_valid(pud_pte(pud))
static inline void set_pud(pud_t *pudp, pud_t pud)