From: Heiko Carstens Date: Tue, 24 Oct 2023 08:15:19 +0000 (+0200) Subject: s390/cmma: fix detection of DAT pages X-Git-Tag: v6.6.7~647 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7453e81061a492085f00e9d3bcb26a95217577d9;p=platform%2Fkernel%2Flinux-starfive.git s390/cmma: fix detection of DAT pages commit 44d93045247661acbd50b1629e62f415f2747577 upstream. If the cmma no-dat feature is available the kernel page tables are walked to identify and mark all pages which are used for address translation (all region, segment, and page tables). In a subsequent loop all other pages are marked as "no-dat" pages with the ESSA instruction. This information is visible to the hypervisor, so that the hypervisor can optimize purging of guest TLB entries. The initial loop however is incorrect: only the first three of the four pages which belong to segment and region tables will be marked as being used for DAT. The last page is incorrectly marked as no-dat. This can result in incorrect guest TLB flushes. Fix this by simply marking all four pages. Cc: Reviewed-by: Claudio Imbrenda Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/s390/mm/page-states.c b/arch/s390/mm/page-states.c index 1e2ea70..00e7b08 100644 --- a/arch/s390/mm/page-states.c +++ b/arch/s390/mm/page-states.c @@ -121,7 +121,7 @@ static void mark_kernel_pud(p4d_t *p4d, unsigned long addr, unsigned long end) continue; if (!pud_folded(*pud)) { page = phys_to_page(pud_val(*pud)); - for (i = 0; i < 3; i++) + for (i = 0; i < 4; i++) set_bit(PG_arch_1, &page[i].flags); } mark_kernel_pmd(pud, addr, next); @@ -142,7 +142,7 @@ static void mark_kernel_p4d(pgd_t *pgd, unsigned long addr, unsigned long end) continue; if (!p4d_folded(*p4d)) { page = phys_to_page(p4d_val(*p4d)); - for (i = 0; i < 3; i++) + for (i = 0; i < 4; i++) set_bit(PG_arch_1, &page[i].flags); } mark_kernel_pud(p4d, addr, next); @@ -164,7 +164,7 @@ static void mark_kernel_pgd(void) continue; if (!pgd_folded(*pgd)) { page = phys_to_page(pgd_val(*pgd)); - for (i = 0; i < 3; i++) + for (i = 0; i < 4; i++) set_bit(PG_arch_1, &page[i].flags); } mark_kernel_p4d(pgd, addr, next);