From 959b4fdfe7e27bcf101e2381e500e4076f2bb9ce Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 2 May 2007 19:27:16 +0200 Subject: [PATCH] [PATCH] i386: PARAVIRT: Allow boot-time disable of paravirt_ops patching Add "noreplace-paravirt" to disable paravirt_ops patching. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Andi Kleen Cc: Rusty Russell Cc: Andi Kleen Signed-off-by: Andrew Morton --- Documentation/kernel-parameters.txt | 3 +++ arch/i386/kernel/alternative.c | 13 +++++++++++++ 2 files changed, 16 insertions(+) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 242b3a09b6c..38d7db3262c 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -64,6 +64,7 @@ parameter is applicable: GENERIC_TIME The generic timeofday code is enabled. NFS Appropriate NFS support is enabled. OSS OSS sound support is enabled. + PV_OPS A paravirtualized kernel PARIDE The ParIDE subsystem is enabled. PARISC The PA-RISC architecture is enabled. PCI PCI bus support is enabled. @@ -1164,6 +1165,8 @@ and is between 256 and 4096 characters. It is defined in the file nomce [IA-32] Machine Check Exception + noreplace-paravirt [IA-32,PV_OPS] Don't patch paravirt_ops + noreplace-smp [IA-32,SMP] Don't replace SMP instructions with UP alternatives diff --git a/arch/i386/kernel/alternative.c b/arch/i386/kernel/alternative.c index c5d037c6095..080a59d56ea 100644 --- a/arch/i386/kernel/alternative.c +++ b/arch/i386/kernel/alternative.c @@ -30,6 +30,16 @@ static int __init setup_noreplace_smp(char *str) } __setup("noreplace-smp", setup_noreplace_smp); +#ifdef CONFIG_PARAVIRT +static int noreplace_paravirt = 0; + +static int __init setup_noreplace_paravirt(char *str) +{ + noreplace_paravirt = 1; + return 1; +} +__setup("noreplace-paravirt", setup_noreplace_paravirt); +#endif #define DPRINTK(fmt, args...) if (debug_alternative) \ printk(KERN_DEBUG fmt, args) @@ -330,6 +340,9 @@ void apply_paravirt(struct paravirt_patch_site *start, { struct paravirt_patch_site *p; + if (noreplace_paravirt) + return; + for (p = start; p < end; p++) { unsigned int used;