diff options
Diffstat (limited to '0003-x86-xen-init-gs-very-early-to-avoid-page-faults-with.patch')
| -rw-r--r-- | 0003-x86-xen-init-gs-very-early-to-avoid-page-faults-with.patch | 80 |
1 files changed, 0 insertions, 80 deletions
diff --git a/0003-x86-xen-init-gs-very-early-to-avoid-page-faults-with.patch b/0003-x86-xen-init-gs-very-early-to-avoid-page-faults-with.patch deleted file mode 100644 index 4b490730e3c3..000000000000 --- a/0003-x86-xen-init-gs-very-early-to-avoid-page-faults-with.patch +++ /dev/null @@ -1,80 +0,0 @@ -From cd0c80aa02dbfe649c743fa98fcc0d9f427e0827 Mon Sep 17 00:00:00 2001 -Message-Id: <cd0c80aa02dbfe649c743fa98fcc0d9f427e0827.1518828081.git.jan.steffens@gmail.com> -In-Reply-To: <05a43fb8b36cdaf6a3580f46cab334f2c2796544.1518828081.git.jan.steffens@gmail.com> -References: <05a43fb8b36cdaf6a3580f46cab334f2c2796544.1518828081.git.jan.steffens@gmail.com> -From: Juergen Gross <jgross@suse.com> -Date: Thu, 1 Feb 2018 13:40:19 +0100 -Subject: [PATCH 3/3] x86/xen: init %gs very early to avoid page faults with - stack protector - -When running as Xen pv guest %gs is initialized some time after -C code is started. Depending on stack protector usage this might be -too late, resulting in page faults. - -So setup %gs and MSR_GS_BASE in assembly code already. - -Cc: stable@vger.kernel.org -Signed-off-by: Juergen Gross <jgross@suse.com> -Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> -Tested-by: Chris Patterson <cjp256@gmail.com> -Signed-off-by: Juergen Gross <jgross@suse.com> ---- - arch/x86/xen/xen-head.S | 16 ++++++++++++++++ - 1 file changed, 16 insertions(+) - -diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S -index 497cc55a0c16..96f26e026783 100644 ---- a/arch/x86/xen/xen-head.S -+++ b/arch/x86/xen/xen-head.S -@@ -9,32 +9,48 @@ - - #include <asm/boot.h> - #include <asm/asm.h> -+#include <asm/msr.h> - #include <asm/page_types.h> -+#include <asm/percpu.h> - #include <asm/unwind_hints.h> - - #include <xen/interface/elfnote.h> - #include <xen/interface/features.h> - #include <xen/interface/xen.h> - #include <xen/interface/xen-mca.h> - #include <asm/xen/interface.h> - - #ifdef CONFIG_XEN_PV - __INIT - ENTRY(startup_xen) - UNWIND_HINT_EMPTY - cld - - /* Clear .bss */ - xor %eax,%eax - mov $__bss_start, %_ASM_DI - mov $__bss_stop, %_ASM_CX - sub %_ASM_DI, %_ASM_CX - shr $__ASM_SEL(2, 3), %_ASM_CX - rep __ASM_SIZE(stos) - - mov %_ASM_SI, xen_start_info - mov $init_thread_union+THREAD_SIZE, %_ASM_SP - -+#ifdef CONFIG_X86_64 -+ /* Set up %gs. -+ * -+ * The base of %gs always points to the bottom of the irqstack -+ * union. If the stack protector canary is enabled, it is -+ * located at %gs:40. Note that, on SMP, the boot cpu uses -+ * init data section till per cpu areas are set up. -+ */ -+ movl $MSR_GS_BASE,%ecx -+ movq $INIT_PER_CPU_VAR(irq_stack_union),%rax -+ cdq -+ wrmsr -+#endif -+ - jmp xen_start_kernel - END(startup_xen) - __FINIT --- -2.16.1 - |