diff options
authorJosh Boyer <jwboyer@redhat.com>2013-04-18 07:51:34 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-10-05 07:06:53 -0700
commit96c3df85670b3cf3e070b3065b8b616305bc3208 (patch)
parentd0878f4565ee60ea6413ab1ad2e67e4a78ea17f6 (diff)
x86, efi: Don't map Boot Services on i386
commit 700870119f49084da004ab588ea2b799689efaf7 upstream. Add patch to fix 32bit EFI service mapping (rhbz 726701) Multiple people are reporting hitting the following WARNING on i386, WARNING: at arch/x86/mm/ioremap.c:102 __ioremap_caller+0x3d3/0x440() Modules linked in: Pid: 0, comm: swapper Not tainted 3.9.0-rc7+ #95 Call Trace: [<c102b6af>] warn_slowpath_common+0x5f/0x80 [<c1023fb3>] ? __ioremap_caller+0x3d3/0x440 [<c1023fb3>] ? __ioremap_caller+0x3d3/0x440 [<c102b6ed>] warn_slowpath_null+0x1d/0x20 [<c1023fb3>] __ioremap_caller+0x3d3/0x440 [<c106007b>] ? get_usage_chars+0xfb/0x110 [<c102d937>] ? vprintk_emit+0x147/0x480 [<c1418593>] ? efi_enter_virtual_mode+0x1e4/0x3de [<c102406a>] ioremap_cache+0x1a/0x20 [<c1418593>] ? efi_enter_virtual_mode+0x1e4/0x3de [<c1418593>] efi_enter_virtual_mode+0x1e4/0x3de [<c1407984>] start_kernel+0x286/0x2f4 [<c1407535>] ? repair_env_string+0x51/0x51 [<c1407362>] i386_start_kernel+0x12c/0x12f Due to the workaround described in commit 916f676f8 ("x86, efi: Retain boot service code until after switching to virtual mode") EFI Boot Service regions are mapped for a period during boot. Unfortunately, with the limited size of the i386 direct kernel map it's possible that some of the Boot Service regions will not be directly accessible, which causes them to be ioremap()'d, triggering the above warning as the regions are marked as E820_RAM in the e820 memmap. There are currently only two situations where we need to map EFI Boot Service regions, 1. To workaround the firmware bug described in 916f676f8 2. To access the ACPI BGRT image but since we haven't seen an i386 implementation that requires either, this simple fix should suffice for now. [ Added to changelog - Matt ] Reported-by: Bryan O'Donoghue <bryan.odonoghue.lkml@nexus-software.ie> Acked-by: Tom Zanussi <tom.zanussi@intel.com> Acked-by: Darren Hart <dvhart@linux.intel.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Josh Boyer <jwboyer@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 7 insertions, 4 deletions
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 1e406371a683..454548c309f1 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -845,10 +845,13 @@ void __init efi_enter_virtual_mode(void)
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
md = p;
- if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
- md->type != EFI_BOOT_SERVICES_CODE &&
- continue;
+ if (!(md->attribute & EFI_MEMORY_RUNTIME)) {
+#ifdef CONFIG_X86_64
+ if (md->type != EFI_BOOT_SERVICES_CODE &&
+ continue;
+ }
size = md->num_pages << EFI_PAGE_SHIFT;
end = md->phys_addr + size;