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| author | Andy Lutomirski <luto@amacapital.net> | 2014-05-05 12:19:33 -0700 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2014-05-05 13:18:47 -0700 |
| commit | cfda7bb9ecbf9d96264bb5bade33a842966d1062 (patch) | |
| tree | 847dca2ec3bfccc701a9e9dd4cb74a48c9afc3b6 /arch/x86/kernel/cpu/common.c | |
| parent | 3d7ee969bffcc984c8aeaffc6ac6816fd929ace1 (diff) | |
| download | op-kernel-dev-cfda7bb9ecbf9d96264bb5bade33a842966d1062.zip op-kernel-dev-cfda7bb9ecbf9d96264bb5bade33a842966d1062.tar.gz | |
x86, vdso: Move syscall and sysenter setup into kernel/cpu/common.c
This code is used during CPU setup, and it isn't strictly speaking
related to the 32-bit vdso. It's easier to understand how this
works when the code is closer to its callers.
This also lets syscall32_cpu_init be static, which might save some
trivial amount of kernel text.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/4e466987204e232d7b55a53ff6b9739f12237461.1399317206.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index a135239..7c65b46 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -953,6 +953,38 @@ static void vgetcpu_set_mode(void) else vgetcpu_mode = VGETCPU_LSL; } + +/* May not be __init: called during resume */ +static void syscall32_cpu_init(void) +{ + /* Load these always in case some future AMD CPU supports + SYSENTER from compat mode too. */ + wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS); + wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL); + wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)ia32_sysenter_target); + + wrmsrl(MSR_CSTAR, ia32_cstar_target); +} +#endif + +#ifdef CONFIG_X86_32 +void enable_sep_cpu(void) +{ + int cpu = get_cpu(); + struct tss_struct *tss = &per_cpu(init_tss, cpu); + + if (!boot_cpu_has(X86_FEATURE_SEP)) { + put_cpu(); + return; + } + + tss->x86_tss.ss1 = __KERNEL_CS; + tss->x86_tss.sp1 = sizeof(struct tss_struct) + (unsigned long) tss; + wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0); + wrmsr(MSR_IA32_SYSENTER_ESP, tss->x86_tss.sp1, 0); + wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long) ia32_sysenter_target, 0); + put_cpu(); +} #endif void __init identify_boot_cpu(void) |
