diff options
Diffstat (limited to '0001-arm64-account-for-sparsemem-section-alignment-when-c.patch')
| -rw-r--r-- | 0001-arm64-account-for-sparsemem-section-alignment-when-c.patch | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/0001-arm64-account-for-sparsemem-section-alignment-when-c.patch b/0001-arm64-account-for-sparsemem-section-alignment-when-c.patch new file mode 100644 index 000000000..78e01defa --- /dev/null +++ b/0001-arm64-account-for-sparsemem-section-alignment-when-c.patch @@ -0,0 +1,54 @@ +From b3ffe8a6522dd1f07c181a5f2581142776e2162d Mon Sep 17 00:00:00 2001 +From: Ard Biesheuvel <ard.biesheuvel@linaro.org> +Date: Tue, 8 Mar 2016 21:09:29 +0700 +Subject: [PATCH] arm64: account for sparsemem section alignment when choosing + vmemmap offset + +Commit dfd55ad85e4a ("arm64: vmemmap: use virtual projection of linear +region") fixed an issue where the struct page array would overflow into the +adjacent virtual memory region if system RAM was placed so high up in +physical memory that its addresses were not representable in the build time +configured virtual address size. + +However, the fix failed to take into account that the vmemmap region needs +to be relatively aligned with respect to the sparsemem section size, so that +a sequence of page structs corresponding with a sparsemem section in the +linear region appears naturally aligned in the vmemmap region. + +So round up vmemmap to sparsemem section size. Since this essentially moves +the projection of the linear region up in memory, also revert the reduction +of the size of the vmemmap region. + +Fixes: dfd55ad85e4a ("arm64: vmemmap: use virtual projection of linear region") +Tested-by: Mark Langsdorf <mlangsdo@redhat.com> +Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> +--- + arch/arm64/include/asm/pgtable.h | 5 +++-- + 1 file changed, 3 insertions(+), 2 deletions(-) + +diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h +index fc9f7ef..eaa9cab 100644 +--- a/arch/arm64/include/asm/pgtable.h ++++ b/arch/arm64/include/asm/pgtable.h +@@ -40,7 +40,7 @@ + * VMALLOC_END: extends to the available space below vmmemmap, PCI I/O space, + * fixed mappings and modules + */ +-#define VMEMMAP_SIZE ALIGN((1UL << (VA_BITS - PAGE_SHIFT - 1)) * sizeof(struct page), PUD_SIZE) ++#define VMEMMAP_SIZE ALIGN((1UL << (VA_BITS - PAGE_SHIFT)) * sizeof(struct page), PUD_SIZE) + + #ifndef CONFIG_KASAN + #define VMALLOC_START (VA_START) +@@ -52,7 +52,8 @@ + #define VMALLOC_END (PAGE_OFFSET - PUD_SIZE - VMEMMAP_SIZE - SZ_64K) + + #define VMEMMAP_START (VMALLOC_END + SZ_64K) +-#define vmemmap ((struct page *)VMEMMAP_START - (memstart_addr >> PAGE_SHIFT)) ++#define vmemmap ((struct page *)VMEMMAP_START - \ ++ SECTION_ALIGN_DOWN(memstart_addr >> PAGE_SHIFT)) + + #define FIRST_USER_ADDRESS 0UL + +-- +2.5.0 + |