diff options
| author | Luis R. Rodriguez <mcgrof@kernel.org> | 2016-04-14 03:04:36 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-04-22 11:29:02 +0300 |
| commit | 1330e3bc544a1951d81b7f3c7d4cecf77d906f67 (patch) | |
| tree | 0ed350c36e9576c6661f38956ef602e8af52092b /arch/x86 | |
| parent | 088a8ef8207f19aadbade0971af21ad89fdc3815 (diff) | |
| download | linux-1330e3bc544a1951d81b7f3c7d4cecf77d906f67.tar.xz | |
x86/init: Use a platform legacy quirk for EBDA
This replaces the paravirt_enabled() check with a
proper x86 legacy platform quirk.
As per 0-day, this bumps the vmlinux size using i386-tinyconfig as
follows:
TOTAL TEXT init.text x86_early_init_platform_quirks()
+39 +35 +35 +25
That's a 4 byte total overhead, the rest is all cleared out
upon init as its all __init text.
v2: document 0-day vmlinux size impact
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andrew.cooper3@citrix.com
Cc: andriy.shevchenko@linux.intel.com
Cc: bigeasy@linutronix.de
Cc: boris.ostrovsky@oracle.com
Cc: david.vrabel@citrix.com
Cc: ffainelli@freebox.fr
Cc: george.dunlap@citrix.com
Cc: glin@suse.com
Cc: jgross@suse.com
Cc: jlee@suse.com
Cc: josh@joshtriplett.org
Cc: julien.grall@linaro.org
Cc: konrad.wilk@oracle.com
Cc: kozerkov@parallels.com
Cc: lenb@kernel.org
Cc: lguest@lists.ozlabs.org
Cc: linux-acpi@vger.kernel.org
Cc: lv.zheng@intel.com
Cc: matt@codeblueprint.co.uk
Cc: mbizon@freebox.fr
Cc: rjw@rjwysocki.net
Cc: robert.moore@intel.com
Cc: rusty@rustcorp.com.au
Cc: tiwai@suse.de
Cc: toshi.kani@hp.com
Cc: xen-devel@lists.xensource.com
Link: http://lkml.kernel.org/r/1460592286-300-7-git-send-email-mcgrof@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/include/asm/x86_init.h | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/head.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/platform-quirks.c | 4 |
3 files changed, 8 insertions, 1 deletions
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h index 8bb8c1a4615a..89d9d57e145d 100644 --- a/arch/x86/include/asm/x86_init.h +++ b/arch/x86/include/asm/x86_init.h @@ -145,9 +145,12 @@ struct timespec; * struct x86_legacy_features - legacy x86 features * * @rtc: this device has a CMOS real-time clock present + * @ebda_search: it's safe to search for the EBDA signature in the hardware's + * low RAM */ struct x86_legacy_features { int rtc; + int ebda_search; }; /** diff --git a/arch/x86/kernel/head.c b/arch/x86/kernel/head.c index 992f442ca155..afe65dffee80 100644 --- a/arch/x86/kernel/head.c +++ b/arch/x86/kernel/head.c @@ -38,7 +38,7 @@ void __init reserve_ebda_region(void) * that the paravirt case can handle memory setup * correctly, without our help. */ - if (paravirt_enabled()) + if (!x86_platform.legacy.ebda_search) return; /* end of low (conventional) memory */ diff --git a/arch/x86/kernel/platform-quirks.c b/arch/x86/kernel/platform-quirks.c index 021a5f973ce3..01b159781d96 100644 --- a/arch/x86/kernel/platform-quirks.c +++ b/arch/x86/kernel/platform-quirks.c @@ -7,8 +7,12 @@ void __init x86_early_init_platform_quirks(void) { x86_platform.legacy.rtc = 1; + x86_platform.legacy.ebda_search = 0; switch (boot_params.hdr.hardware_subarch) { + case X86_SUBARCH_PC: + x86_platform.legacy.ebda_search = 1; + break; case X86_SUBARCH_XEN: case X86_SUBARCH_LGUEST: case X86_SUBARCH_INTEL_MID: |