Re: [PATCH RFC v8 19/56] x86/fault: Return pfn from dump_pagetable() for SEV-specific fault handling.
From: Zhi Wang <zhi.wang.linux@gmail.com>
Date: 2023-02-20 21:13:24
Also in:
kvm, linux-crypto, linux-mm, lkml
On Mon, 20 Feb 2023 12:38:10 -0600 Michael Roth [off-list ref] wrote:
From: Ashish Kalra <ashish.kalra@amd.com> Return pfn from dump_pagetable() to do SEV-specific fault handling. Used for handling SNP RMP page fault.
It would be better to merge this patch with PATCH 13.
quoted hunk ↗ jump to hunk
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Signed-off-by: Michael Roth <redacted> --- arch/x86/mm/fault.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index afd4cde17001..f2b16dcfbd9a 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c@@ -311,7 +311,7 @@ static bool low_pfn(unsigned long pfn) return pfn < max_low_pfn; } -static void dump_pagetable(unsigned long address) +static unsigned long dump_pagetable(unsigned long address) { pgd_t *base = __va(read_cr3_pa()); pgd_t *pgd = &base[pgd_index(address)];@@ -345,8 +345,10 @@ static void dump_pagetable(unsigned long address) pte = pte_offset_kernel(pmd, address); pr_cont("*pte = %0*Lx ", sizeof(*pte) * 2, (u64)pte_val(*pte)); + return 0; out: pr_cont("\n"); + return 0; } #else /* CONFIG_X86_64: */@@ -367,10 +369,11 @@ static int bad_address(void *p) return get_kernel_nofault(dummy, (unsigned long *)p); } -static void dump_pagetable(unsigned long address) +static unsigned long dump_pagetable(unsigned long address) { pgd_t *base = __va(read_cr3_pa()); pgd_t *pgd = base + pgd_index(address); + unsigned long pfn; p4d_t *p4d; pud_t *pud; pmd_t *pmd;@@ -388,6 +391,7 @@ static void dump_pagetable(unsigned long address) if (bad_address(p4d)) goto bad; + pfn = p4d_pfn(*p4d); pr_cont("P4D %lx ", p4d_val(*p4d)); if (!p4d_present(*p4d) || p4d_large(*p4d)) goto out;@@ -396,6 +400,7 @@ static void dump_pagetable(unsigned long address) if (bad_address(pud)) goto bad; + pfn = pud_pfn(*pud); pr_cont("PUD %lx ", pud_val(*pud)); if (!pud_present(*pud) || pud_large(*pud)) goto out;@@ -404,6 +409,7 @@ static void dump_pagetable(unsigned long address) if (bad_address(pmd)) goto bad; + pfn = pmd_pfn(*pmd); pr_cont("PMD %lx ", pmd_val(*pmd)); if (!pmd_present(*pmd) || pmd_large(*pmd)) goto out;@@ -412,13 +418,14 @@ static void dump_pagetable(unsigned long address) if (bad_address(pte)) goto bad; + pfn = pte_pfn(*pte); pr_cont("PTE %lx", pte_val(*pte)); out: pr_cont("\n"); - - return; + return pfn; bad: pr_info("BAD\n"); + return -1; } #endif /* CONFIG_X86_64 */