linux/arch/x86/platform
Andy Lutomirski 5bc653b731 x86/efi: Allocate a trampoline if needed in efi_free_boot_services()
On my Dell XPS 13 9350 with firmware 1.4.4 and SGX on, if I boot
Fedora 24's grub2-efi off a hard disk, my first 1MB of RAM looks
like:

 efi: mem00: [Runtime Data       |RUN|  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000000000000-0x0000000000000fff] (0MB)
 efi: mem01: [Boot Data          |   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000000001000-0x0000000000027fff] (0MB)
 efi: mem02: [Loader Data        |   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000000028000-0x0000000000029fff] (0MB)
 efi: mem03: [Reserved           |   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x000000000002a000-0x000000000002bfff] (0MB)
 efi: mem04: [Runtime Data       |RUN|  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x000000000002c000-0x000000000002cfff] (0MB)
 efi: mem05: [Loader Data        |   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x000000000002d000-0x000000000002dfff] (0MB)
 efi: mem06: [Conventional Memory|   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x000000000002e000-0x0000000000057fff] (0MB)
 efi: mem07: [Reserved           |   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000000058000-0x0000000000058fff] (0MB)
 efi: mem08: [Conventional Memory|   |  |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000000059000-0x000000000009ffff] (0MB)

My EBDA is at 0x2c000, which blocks off everything from 0x2c000 and
up, and my trampoline is 0x6000 bytes (6 pages), so it doesn't fit
in the loader data range at 0x28000.

Without this patch, it panics due to a failure to allocate the
trampoline.  With this patch, it works:

 [  +0.001744] Base memory trampoline at [ffff880000001000] 1000 size 24576

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/998c77b3bf709f3dfed85cb30701ed1a5d8a438b.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 13:53:07 +02:00
..
atom x86/platform/atom/punit: Enable support for Merrifield 2016-06-14 12:44:51 +02:00
ce4100 x86/ce4100: Remove duplicated include from ce4100.c 2016-07-19 16:02:17 +02:00
efi x86/efi: Allocate a trampoline if needed in efi_free_boot_services() 2016-08-11 13:53:07 +02:00
geode x86/platform: Make platform/geode/net5501.c explicitly non-modular 2016-02-16 09:11:09 +01:00
goldfish goldfish: platform device for x86 2013-01-21 12:09:19 -08:00
intel x86/platform/iosf_mbi: Add Intel Tangier PCI id 2015-07-16 17:48:48 +02:00
intel-mid RTC for 4.8 2016-08-05 09:48:22 -04:00
intel-quark x86/platform/intel/quark: Drop IMR lock bit support 2016-02-23 07:37:23 +01:00
iris x86: platform: iris: drop owner assignment from platform_drivers 2014-10-20 16:20:15 +02:00
olpc x86/platform: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:59 +02:00
scx200 X86: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
sfi x86: Cleanup irq_domain ops 2015-04-24 15:36:55 +02:00
ts5500 x86/platform: Delete extraneous MODULE_* tags fromm ts5500 2016-07-16 22:41:00 +02:00
uv x86/platform/UV: Fix bug with iounmap() of the UV4 EFI System Table causing a crash 2016-08-10 15:55:38 +02:00
Makefile x86/platform/iosf_mbi: Move to dedicated folder 2015-07-16 17:48:47 +02:00