diff options
| -rw-r--r-- | queue-5.10/arm64-restrict-pagetable-teardown-to-avoid-false-warning.patch | 46 | ||||
| -rw-r--r-- | queue-5.10/series | 1 |
2 files changed, 47 insertions, 0 deletions
diff --git a/queue-5.10/arm64-restrict-pagetable-teardown-to-avoid-false-warning.patch b/queue-5.10/arm64-restrict-pagetable-teardown-to-avoid-false-warning.patch new file mode 100644 index 0000000000..440cd026d8 --- /dev/null +++ b/queue-5.10/arm64-restrict-pagetable-teardown-to-avoid-false-warning.patch @@ -0,0 +1,46 @@ +From 650768c512faba8070bf4cfbb28c95eb5cd203f3 Mon Sep 17 00:00:00 2001 +From: Dev Jain <dev.jain@arm.com> +Date: Tue, 27 May 2025 13:56:33 +0530 +Subject: arm64: Restrict pagetable teardown to avoid false warning + +From: Dev Jain <dev.jain@arm.com> + +commit 650768c512faba8070bf4cfbb28c95eb5cd203f3 upstream. + +Commit 9c006972c3fe ("arm64: mmu: drop pXd_present() checks from +pXd_free_pYd_table()") removes the pxd_present() checks because the +caller checks pxd_present(). But, in case of vmap_try_huge_pud(), the +caller only checks pud_present(); pud_free_pmd_page() recurses on each +pmd through pmd_free_pte_page(), wherein the pmd may be none. Thus it is +possible to hit a warning in the latter, since pmd_none => !pmd_table(). +Thus, add a pmd_present() check in pud_free_pmd_page(). + +This problem was found by code inspection. + +Fixes: 9c006972c3fe ("arm64: mmu: drop pXd_present() checks from pXd_free_pYd_table()") +Cc: stable@vger.kernel.org +Reported-by: Ryan Roberts <ryan.roberts@arm.com> +Acked-by: David Hildenbrand <david@redhat.com> +Signed-off-by: Dev Jain <dev.jain@arm.com> +Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> +Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> +Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> +Link: https://lore.kernel.org/r/20250527082633.61073-1-dev.jain@arm.com +Signed-off-by: Will Deacon <will@kernel.org> +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + arch/arm64/mm/mmu.c | 3 ++- + 1 file changed, 2 insertions(+), 1 deletion(-) + +--- a/arch/arm64/mm/mmu.c ++++ b/arch/arm64/mm/mmu.c +@@ -1459,7 +1459,8 @@ int pud_free_pmd_page(pud_t *pudp, unsig + next = addr; + end = addr + PUD_SIZE; + do { +- pmd_free_pte_page(pmdp, next); ++ if (pmd_present(READ_ONCE(*pmdp))) ++ pmd_free_pte_page(pmdp, next); + } while (pmdp++, next += PMD_SIZE, next != end); + + pud_clear(pudp); diff --git a/queue-5.10/series b/queue-5.10/series index 61d6145bda..f9c3f9fed4 100644 --- a/queue-5.10/series +++ b/queue-5.10/series @@ -77,3 +77,4 @@ drm-bridge-cdns-dsi-wait-for-clk-and-data-lanes-to-be-ready.patch pci-hv-do-not-set-pci_command_memory-to-reduce-vm-boot-time.patch s390-add-std-gnu11-to-decompressor-and-purgatory-cflags.patch revert-ipv6-save-dontfrag-in-cork.patch +arm64-restrict-pagetable-teardown-to-avoid-false-warning.patch |