From ce2eef33d35cd7b932492b5a81fb0febd2b323cd Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 17 Aug 2009 12:26:53 -0700 Subject: xen: rearrange things to fix stackprotector Make sure the stack-protector segment registers are properly set up before calling any functions which may have stack-protection compiled into them. [ Impact: prevent Xen early-boot crash when stack-protector is enabled ] Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/enlighten.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) (limited to 'arch/x86/xen/enlighten.c') diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index f09e8c36ee8..edcf72a3c29 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -925,10 +925,6 @@ asmlinkage void __init xen_start_kernel(void) xen_domain_type = XEN_PV_DOMAIN; - BUG_ON(memcmp(xen_start_info->magic, "xen-3", 5) != 0); - - xen_setup_features(); - /* Install Xen paravirt ops */ pv_info = xen_info; pv_init_ops = xen_init_ops; @@ -937,8 +933,15 @@ asmlinkage void __init xen_start_kernel(void) pv_apic_ops = xen_apic_ops; pv_mmu_ops = xen_mmu_ops; - xen_init_irq_ops(); +#ifdef CONFIG_X86_64 + /* + * Setup percpu state. We only need to do this for 64-bit + * because 32-bit already has %fs set properly. + */ + load_percpu_segment(0); +#endif + xen_init_irq_ops(); xen_init_cpuid_mask(); #ifdef CONFIG_X86_LOCAL_APIC @@ -948,6 +951,8 @@ asmlinkage void __init xen_start_kernel(void) set_xen_basic_apic_ops(); #endif + xen_setup_features(); + if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) { pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start; pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit; @@ -955,13 +960,6 @@ asmlinkage void __init xen_start_kernel(void) machine_ops = xen_machine_ops; -#ifdef CONFIG_X86_64 - /* - * Setup percpu state. We only need to do this for 64-bit - * because 32-bit already has %fs set properly. - */ - load_percpu_segment(0); -#endif /* * The only reliable way to retain the initial address of the * percpu gdt_page is to remember it here, so we can go and -- cgit v1.2.3-70-g09d2 From d560bc61575efae43595cbcb56d0ba3b9450139c Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 25 Aug 2009 12:53:02 -0700 Subject: x86, xen: Suppress WP test on Xen Xen always runs on CPUs which properly support WP enforcement in privileged mode, so there's no need to test for it. This also works around a crash reported by Arnd Hannemann, though I think its just a band-aid for that case. Reported-by: Arnd Hannemann Signed-off-by: Jeremy Fitzhardinge Acked-by: Pekka Enberg Signed-off-by: H. Peter Anvin --- arch/x86/xen/enlighten.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/xen/enlighten.c') diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index e90540a46a0..0b755cd7686 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1059,6 +1059,7 @@ asmlinkage void __init xen_start_kernel(void) /* set up basic CPUID stuff */ cpu_detect(&new_cpu_data); new_cpu_data.hard_math = 1; + new_cpu_data.wp_works_ok = 1; new_cpu_data.x86_capability[0] = cpuid_edx(1); #endif -- cgit v1.2.3-70-g09d2 From 7adb4df410966dfe43e4815256e3215110648fb8 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Tue, 25 Aug 2009 21:06:03 -0700 Subject: x86, xen: Initialize cx to suppress warning Initialize cx before calling xen_cpuid(), in order to suppress the "may be used uninitialized in this function" warning. Signed-off-by: H. Peter Anvin Cc: Jeremy Fitzhardinge --- arch/x86/xen/enlighten.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/xen/enlighten.c') diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 0b755cd7686..eb33aaa8415 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -215,6 +215,7 @@ static __init void xen_init_cpuid_mask(void) (1 << X86_FEATURE_ACPI)); /* disable ACPI */ ax = 1; + cx = 0; xen_cpuid(&ax, &bx, &cx, &dx); /* cpuid claims we support xsave; try enabling it to see what happens */ -- cgit v1.2.3-70-g09d2