diff options
Diffstat (limited to 'efi-arm64-don-t-apply-MEMBLOCK_NOMAP-to-UEFI-memory-map-mapping.patch')
| -rw-r--r-- | efi-arm64-don-t-apply-MEMBLOCK_NOMAP-to-UEFI-memory-map-mapping.patch | 92 |
1 files changed, 0 insertions, 92 deletions
diff --git a/efi-arm64-don-t-apply-MEMBLOCK_NOMAP-to-UEFI-memory-map-mapping.patch b/efi-arm64-don-t-apply-MEMBLOCK_NOMAP-to-UEFI-memory-map-mapping.patch deleted file mode 100644 index 2e3ae0c9b..000000000 --- a/efi-arm64-don-t-apply-MEMBLOCK_NOMAP-to-UEFI-memory-map-mapping.patch +++ /dev/null @@ -1,92 +0,0 @@ -From patchwork Wed Mar 30 07:46:23 2016 -Content-Type: text/plain; charset="utf-8" -MIME-Version: 1.0 -Content-Transfer-Encoding: 7bit -Subject: efi/arm64: don't apply MEMBLOCK_NOMAP to UEFI memory map mapping -From: Ard Biesheuvel <ard.biesheuvel@linaro.org> -X-Patchwork-Id: 8693271 -Message-Id: <1459323983-9120-1-git-send-email-ard.biesheuvel@linaro.org> -To: linux-efi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, - matt@codeblueprint.co.uk -Cc: mark.rutland@arm.com, mlangsdo@redhat.com, - Ard Biesheuvel <ard.biesheuvel@linaro.org>, leif.lindholm@linaro.org, - jeremy.linton@arm.com, msalter@redhat.com -Date: Wed, 30 Mar 2016 09:46:23 +0200 - -Hi Matt, - -Could we queue this as a fix for v4.6 with a cc:stable for v4.5, please? -(assuming no objections from any of the cc'ees) - -Thanks, -Ard. - -----------8<-------------- -Commit 4dffbfc48d65 ("arm64/efi: mark UEFI reserved regions as -MEMBLOCK_NOMAP") updated the mapping logic of both the RuntimeServices -regions as well as the kernel's copy of the UEFI memory map to set the -MEMBLOCK_NOMAP flag, which causes these regions to be omitted from the -kernel direct mapping, and from being covered by a struct page. -For the RuntimeServices regions, this is an obvious win, since the contents -of these regions have significance to the firmware executable code itself, -and are mapped in the EFI page tables using attributes that are described in -the UEFI memory map, and which may differ from the attributes we use for -mapping system RAM. It also prevents the contents from being modified -inadvertently, since the EFI page tables are only live during runtime -service invocations. - -None of these concerns apply to the allocation that covers the UEFI memory -map, since it is entirely owned by the kernel. Setting the MEMBLOCK_NOMAP on -the region did allow us to use ioremap_cache() to map it both on arm64 and -on ARM, since the latter does not allow ioremap_cache() to be used on -regions that are covered by a struct page. - -The ioremap_cache() on ARM restriction will be lifted in the v4.7 timeframe, -but in the mean time, it has been reported that commit 4dffbfc48d65 causes -a regression on 64k granule kernels. This is due to the fact that, given -the 64 KB page size, the region that we end up removing from the kernel -direct mapping is rounded up to 64 KB, and this 64 KB page frame may be -shared with the initrd when booting via GRUB (which does not align its -EFI_LOADER_DATA allocations to 64 KB like the stub does). This will crash -the kernel as soon as it tries to access the initrd. - -Since the issue is specific to arm64, revert back to memblock_reserve()'ing -the UEFI memory map when running on arm64. This is a temporary fix for v4.5 -and v4.6, and will be superseded in the v4.7 timeframe when we will be able -to move back to memblock_reserve() unconditionally. - -Fixes: 4dffbfc48d65 ("arm64/efi: mark UEFI reserved regions as MEMBLOCK_NOMAP") -Reported-by: Mark Salter <msalter@redhat.com> -Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> - ---- -drivers/firmware/efi/arm-init.c | 18 +++++++++++++++--- - 1 file changed, 15 insertions(+), 3 deletions(-) - -diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c -index aa1f743152a2..8714f8c271ba 100644 ---- a/drivers/firmware/efi/arm-init.c -+++ b/drivers/firmware/efi/arm-init.c -@@ -203,7 +203,19 @@ void __init efi_init(void) - - reserve_regions(); - early_memunmap(memmap.map, params.mmap_size); -- memblock_mark_nomap(params.mmap & PAGE_MASK, -- PAGE_ALIGN(params.mmap_size + -- (params.mmap & ~PAGE_MASK))); -+ -+ if (IS_ENABLED(CONFIG_ARM)) { -+ /* -+ * ARM currently does not allow ioremap_cache() to be called on -+ * memory regions that are covered by struct page. So remove the -+ * UEFI memory map from the linear mapping. -+ */ -+ memblock_mark_nomap(params.mmap & PAGE_MASK, -+ PAGE_ALIGN(params.mmap_size + -+ (params.mmap & ~PAGE_MASK))); -+ } else { -+ memblock_reserve(params.mmap & PAGE_MASK, -+ PAGE_ALIGN(params.mmap_size + -+ (params.mmap & ~PAGE_MASK))); -+ } - } |