From: Chris Bainbridge <chris.bainbridge@gmail.com>
To: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH] x86: set Pentium M as PAE capable
Date: Tue, 25 Feb 2014 13:01:47 +0700 [thread overview]
Message-ID: <20140225060146.GA4339@debian.local> (raw)
Pentium M is PAE capable but does not indicate so in the CPUID response.
This is an issue now that some distributions are no longer shipping
non-PAE kernels (those distributions no longer boot on Pentium M). This
small patch fixes the issue by forcing the PAE capability on Pentium M.
For more discussion see https://bugs.launchpad.net/baltix/+bug/930447
Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
---
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index bbe1b8b..97996aa 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -226,6 +226,12 @@ static void intel_workarounds(struct cpuinfo_x86 *c)
clear_cpu_cap(c, X86_FEATURE_SEP);
/*
+ * PAE CPUID bug: Pentium M reports no PAE but has PAE
+ */
+ if ((c->x86 == 6) && ((c->x86_model == 9) || (c->x86_model == 13)))
+ set_cpu_cap(c, X86_FEATURE_PAE);
+
+ /*
* P4 Xeon errata 037 workaround.
* Hardware prefetcher may cause stale data to be loaded into the cache.
*/
next reply other threads:[~2014-02-25 6:02 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-25 6:01 Chris Bainbridge [this message]
2014-02-25 10:45 ` [PATCH] x86: set Pentium M as PAE capable H. Peter Anvin
2014-02-25 11:35 ` Borislav Petkov
2014-02-25 12:06 ` Peter Hurley
2014-02-25 12:07 ` One Thousand Gnomes
2014-02-25 16:26 ` Dave Jones
2014-02-25 17:16 ` H. Peter Anvin
2014-02-26 12:12 ` Chris Bainbridge
2014-02-26 13:18 ` Borislav Petkov
2014-02-26 15:49 ` Dave Jones
2014-02-26 17:18 ` Borislav Petkov
2014-02-26 17:20 ` Dave Jones
2014-02-26 17:28 ` Borislav Petkov
2014-02-28 7:30 ` Chris Bainbridge
[not found] ` <CAKKYfmFgVjYwvThpB0FBB+ggOwULWKLpz7ADT1eojno_KtD9yw@mail.gmail.com>
2014-02-28 14:00 ` Chris Bainbridge
2014-03-02 20:56 ` Andreas Mohr
2014-03-02 20:59 ` H. Peter Anvin
2014-03-02 21:02 ` Dave Jones
2014-03-02 21:04 ` Borislav Petkov
2014-03-02 21:13 ` Andreas Mohr
2014-03-02 21:42 ` Gene Heskett
2014-03-03 12:31 ` One Thousand Gnomes
2014-03-03 8:04 ` Chris Bainbridge
2014-03-03 19:29 ` Borislav Petkov
2014-03-04 5:01 ` Chris Bainbridge
2014-03-04 5:04 ` H. Peter Anvin
2014-03-04 6:06 ` Chris Bainbridge
2014-03-04 10:44 ` Borislav Petkov
2014-03-05 4:17 ` Chris Bainbridge
2014-03-07 11:40 ` [PATCH] x86: Add forcepae parameter for booting PAE kernels on PAE-disabled Pentium M Chris Bainbridge
2014-03-10 10:25 ` Borislav Petkov
2014-03-20 23:30 ` [tip:x86/cpu] x86, cpu: " tip-bot for Chris Bainbridge
2014-03-20 23:33 ` tip-bot for Chris Bainbridge
2014-03-20 23:30 ` [tip:x86/cpu] Rename TAINT_UNSAFE_SMP to TAINT_CPU_OUT_OF_SPEC tip-bot for Dave Jones
2014-02-26 16:46 ` [PATCH] x86: set Pentium M as PAE capable H. Peter Anvin
2014-02-26 16:44 ` Matthew Garrett
2014-02-26 16:45 ` H. Peter Anvin
2014-02-26 17:10 ` Matthew Garrett
2014-02-26 17:57 ` H. Peter Anvin
2014-03-03 0:11 ` H. Peter Anvin
-- strict thread matches above, loose matches on Subject: below --
2014-03-02 19:05 Roland Kletzing
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