[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20180115123410.846967903@linuxfoundation.org>
Date: Mon, 15 Jan 2018 13:35:19 +0100
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-kernel@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
stable@...r.kernel.org, Andy Lutomirski <luto@...nel.org>,
Borislav Petkov <bpetkov@...e.de>,
Linus Torvalds <torvalds@...ux-foundation.org>,
Peter Zijlstra <peterz@...radead.org>,
Thomas Gleixner <tglx@...utronix.de>,
Ingo Molnar <mingo@...nel.org>,
David Woodhouse <dwmw@...zon.co.uk>
Subject: [PATCH 4.9 80/96] x86/mm/32: Move setup_clear_cpu_cap(X86_FEATURE_PCID) earlier
4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Andy Lutomirski <luto@...nel.org>
commit b8b7abaed7a49b350f8ba659ddc264b04931d581 upstream.
Otherwise we might have the PCID feature bit set during cpu_init().
This is just for robustness. I haven't seen any actual bugs here.
Signed-off-by: Andy Lutomirski <luto@...nel.org>
Cc: Borislav Petkov <bpetkov@...e.de>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Thomas Gleixner <tglx@...utronix.de>
Fixes: cba4671af755 ("x86/mm: Disable PCID on 32-bit kernels")
Link: http://lkml.kernel.org/r/b16dae9d6b0db5d9801ddbebbfd83384097c61f3.1505663533.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@...nel.org>
Signed-off-by: David Woodhouse <dwmw@...zon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
arch/x86/kernel/cpu/bugs.c | 8 --------
arch/x86/kernel/cpu/common.c | 8 ++++++++
2 files changed, 8 insertions(+), 8 deletions(-)
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -22,14 +22,6 @@
void __init check_bugs(void)
{
-#ifdef CONFIG_X86_32
- /*
- * Regardless of whether PCID is enumerated, the SDM says
- * that it can't be enabled in 32-bit mode.
- */
- setup_clear_cpu_cap(X86_FEATURE_PCID);
-#endif
-
identify_boot_cpu();
if (!IS_ENABLED(CONFIG_SMP)) {
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -890,6 +890,14 @@ static void __init early_identify_cpu(st
setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
fpu__init_system(c);
+
+#ifdef CONFIG_X86_32
+ /*
+ * Regardless of whether PCID is enumerated, the SDM says
+ * that it can't be enabled in 32-bit mode.
+ */
+ setup_clear_cpu_cap(X86_FEATURE_PCID);
+#endif
}
void __init early_cpu_init(void)
Powered by blists - more mailing lists