diff options
Diffstat (limited to '0001-x86-efi-always-map-first-physical-page-into-EFI-page.patch')
| -rw-r--r-- | 0001-x86-efi-always-map-first-physical-page-into-EFI-page.patch | 64 |
1 files changed, 0 insertions, 64 deletions
diff --git a/0001-x86-efi-always-map-first-physical-page-into-EFI-page.patch b/0001-x86-efi-always-map-first-physical-page-into-EFI-page.patch deleted file mode 100644 index 55baf9b52..000000000 --- a/0001-x86-efi-always-map-first-physical-page-into-EFI-page.patch +++ /dev/null @@ -1,64 +0,0 @@ -From fb1d9d3f95654f00c4156129f3cd90d3efe32d26 Mon Sep 17 00:00:00 2001 -From: Jiri Kosina <jkosina@suse.cz> -Date: Wed, 25 Jan 2017 20:52:33 +0100 -Subject: [PATCH] x86/efi: always map first physical page into EFI pagetables - -Commit 129766708 ("x86/efi: Only map RAM into EFI page tables if in -mixed-mode") stopped creating 1:1 mapping for all RAM in case of running -in native 64bit mode. - -It turns out though that there are 64bit EFI implementations in the wild -(this particular problem has been reported on Lenovo Yoga 710-11IKB) which -still make use of first physical page for their own private use (which is -what legacy BIOS used to do, but EFI specification doesn't grant any such -right to EFI BIOS ... oh well). - -In case there is no mapping for this particular frame in EFI pagetables, -as soon as firmware tries to make use of it, triple fault occurs and the -system reboots (in case of Yoga 710-11IKB this is very early during boot). - -Fix that by always mapping the first page of physical memory into EFI -pagetables. - -Note: just reverting 129766708 is not enough on v4.9-rc1+ to fix the -regression on affected hardware, as commit ab72a27da ("x86/efi: -Consolidate region mapping logic") later made the first physical frame not -to be mapped anyway. - -Fixes: 129766708 ("x86/efi: Only map RAM into EFI page tables if in mixed-mode") -Cc: stable@kernel.org # v4.8+ -Cc: Waiman Long <waiman.long@hpe.com> -Cc: Borislav Petkov <bp@suse.de> -Cc: Laura Abbott <labbott@redhat.com> -Cc: Vojtech Pavlik <vojtech@ucw.cz> -Reported-by: Hanka Pavlikova <hanka@ucw.cz> -Signed-off-by: Jiri Kosina <jkosina@suse.cz> ---- - arch/x86/platform/efi/efi_64.c | 11 +++++++++++ - 1 file changed, 11 insertions(+) - -diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c -index 319148bd4b05..02ae2abe8b8e 100644 ---- a/arch/x86/platform/efi/efi_64.c -+++ b/arch/x86/platform/efi/efi_64.c -@@ -269,6 +269,17 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) - efi_scratch.use_pgd = true; - - /* -+ * Certain firmware versions are way too sentimental and still believe -+ * they are exclusive and unquestionable owners of first physical page. -+ * Create 1:1 mapping for this page to avoid triple faults during early -+ * boot with such firmware. -+ */ -+ if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, _PAGE_RW)) { -+ pr_err("Failed to create 1:1 mapping of first page\n"); -+ return 1; -+ } -+ -+ /* - * When making calls to the firmware everything needs to be 1:1 - * mapped and addressable with 32-bit pointers. Map the kernel - * text and allocate a new stack because we can't rely on the --- -2.11.0 - |