From 56fc6cb5d59a90e926be994e2532df44f6c4349d Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 16 Dec 2021 20:33:42 +1000 Subject: powerpc/64s/radix: Fix huge vmap false positive commit 467ba14e1660b52a2f9338b484704c461bd23019 upstream. pmd_huge() is defined to false when HUGETLB_PAGE is not configured, but the vmap code still installs huge PMDs. This leads to false bad PMD errors when vunmapping because it is not seen as a huge PTE, and the bad PMD check catches it. The end result may not be much more serious than some bad pmd warning messages, because the pmd_none_or_clear_bad() does what we wanted and clears the huge PTE anyway. Fix this by checking pmd_is_leaf(), which checks for a PTE regardless of config options. The whole huge/large/leaf stuff is a tangled mess but that's kernel-wide and not something we can improve much in arch/powerpc code. pmd_page(), pud_page(), etc., called by vmalloc_to_page() on huge vmaps can similarly trigger a false VM_BUG_ON when CONFIG_HUGETLB_PAGE=n, so those checks are adjusted. The checks were added by commit d6eacedd1f0e ("powerpc/book3s: Use config independent helpers for page table walk"), while implementing a similar fix for other page table walking functions. Fixes: d909f9109c30 ("powerpc/64s/radix: Enable HAVE_ARCH_HUGE_VMAP") Cc: stable@vger.kernel.org # v5.3+ Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211216103342.609192-1-npiggin@gmail.com Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/mm/book3s64/radix_pgtable.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/mm/book3s64/radix_pgtable.c') diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c index ae20add7954a..795d18a84f55 100644 --- a/arch/powerpc/mm/book3s64/radix_pgtable.c +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c @@ -1093,7 +1093,7 @@ int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot) int pud_clear_huge(pud_t *pud) { - if (pud_huge(*pud)) { + if (pud_is_leaf(*pud)) { pud_clear(pud); return 1; } @@ -1140,7 +1140,7 @@ int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot) int pmd_clear_huge(pmd_t *pmd) { - if (pmd_huge(*pmd)) { + if (pmd_is_leaf(*pmd)) { pmd_clear(pmd); return 1; } -- cgit v1.2.3