From 4c360db6ccdb12d82c5c255c90c249970f5d1956 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Thu, 30 Sep 2021 14:35:52 +0200 Subject: [PATCH] xen/x86: adjust xen_set_fixmap() Using __native_set_fixmap() here means guaranteed trap-and-emulate instances the hypervisor has to deal with. Since the virtual address covered by the to be adjusted page table entry is easy to determine (and actually already gets obtained in a special case), simply use an available, easy to invoke hypercall instead. Signed-off-by: Jan Beulich Reviewed-by: Boris Ostrovsky Link: https://lore.kernel.org/r/11fcaea2-ec17-3edd-ecdf-4cdd2d472bd0@suse.com Signed-off-by: Boris Ostrovsky --- arch/x86/xen/mmu_pv.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c index 7b366e2..ad0fbc7 100644 --- a/arch/x86/xen/mmu_pv.c +++ b/arch/x86/xen/mmu_pv.c @@ -2011,6 +2011,7 @@ static unsigned char dummy_mapping[PAGE_SIZE] __page_aligned_bss; static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) { pte_t pte; + unsigned long vaddr; phys >>= PAGE_SHIFT; @@ -2051,15 +2052,15 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) break; } - __native_set_fixmap(idx, pte); + vaddr = __fix_to_virt(idx); + if (HYPERVISOR_update_va_mapping(vaddr, pte, UVMF_INVLPG)) + BUG(); #ifdef CONFIG_X86_VSYSCALL_EMULATION /* Replicate changes to map the vsyscall page into the user pagetable vsyscall mapping. */ - if (idx == VSYSCALL_PAGE) { - unsigned long vaddr = __fix_to_virt(idx); + if (idx == VSYSCALL_PAGE) set_pte_vaddr_pud(level3_user_vsyscall, vaddr, pte); - } #endif } -- 2.7.4