[GIT PULL] x86 fixes

Ingo Molnar
2016-10-28T08:41:15Z

Linus,

Please pull the latest x86-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-urgent-for-linus

# HEAD: 1c27f646b18fb56308dff82784ca61951bad0b48 x86/microcode/AMD: Fix more fallout from CONFIG_RANDOMIZE_MEMORY=y

Misc fixes: three build fixes, an unwinder fix and a microcode loader fix.

Thanks,

Ingo

------------------>
Arnd Bergmann (1):
x86/quirks: Hide maybe-uninitialized warning

Borislav Petkov (1):
x86/microcode/AMD: Fix more fallout from CONFIG_RANDOMIZE_MEMORY=y

Jan Beulich (1):
x86/build: Fix build with older GCC versions

Josh Poimboeuf (1):
x86/unwind: Fix empty stack dereference in guess unwinder

Steven Rostedt (1):
x86: Fix export for mcount and __fentry__

arch/x86/entry/Makefile | 4 ++--
arch/x86/kernel/cpu/microcode/amd.c | 2 +-
arch/x86/kernel/mcount_64.S | 3 ++-
arch/x86/kernel/quirks.c | 3 +--
arch/x86/kernel/unwind_guess.c | 9 ++++++++-
5 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/arch/x86/entry/Makefile b/arch/x86/entry/Makefile
index 77f28ce9c646..9976fcecd17e 100644
--- a/arch/x86/entry/Makefile
+++ b/arch/x86/entry/Makefile
@@ -5,8 +5,8 @@
OBJECT_FILES_NON_STANDARD_entry_$(BITS).o := y
OBJECT_FILES_NON_STANDARD_entry_64_compat.o := y

-CFLAGS_syscall_64.o += -Wno-override-init
-CFLAGS_syscall_32.o += -Wno-override-init
+CFLAGS_syscall_64.o += $(call cc-option,-Wno-override-init,)
+CFLAGS_syscall_32.o += $(call cc-option,-Wno-override-init,)
obj-y := entry_$(BITS).o thunk_$(BITS).o syscall_$(BITS).o
obj-y += common.o

diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 620ab06bcf45..017bda12caae 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -429,7 +429,7 @@ int __init save_microcode_in_initrd_amd(void)
* We need the physical address of the container for both bitness since
* boot_params.hdr.ramdisk_image is a physical address.
*/
- cont = __pa(container);
+ cont = __pa_nodebug(container);
cont_va = container;
#endif

diff --git a/arch/x86/kernel/mcount_64.S b/arch/x86/kernel/mcount_64.S
index efe73aacf966..7b0d3da52fb4 100644
--- a/arch/x86/kernel/mcount_64.S
+++ b/arch/x86/kernel/mcount_64.S
@@ -18,8 +18,10 @@

#ifdef CC_USING_FENTRY
# define function_hook __fentry__
+EXPORT_SYMBOL(__fentry__)
#else
# define function_hook mcount
+EXPORT_SYMBOL(mcount)
#endif

/* All cases save the original rbp (8 bytes) */
@@ -295,7 +297,6 @@ GLOBAL(ftrace_stub)
jmp fgraph_trace
END(function_hook)
#endif /* CONFIG_DYNAMIC_FTRACE */
-EXPORT_SYMBOL(function_hook)
#endif /* CONFIG_FUNCTION_TRACER */

#ifdef CONFIG_FUNCTION_GRAPH_TRACER
diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c
index 51402a7e4ca6..0bee04d41bed 100644
--- a/arch/x86/kernel/quirks.c
+++ b/arch/x86/kernel/quirks.c
@@ -625,8 +625,6 @@ static void amd_disable_seq_and_redirect_scrub(struct pci_dev *dev)
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3,
amd_disable_seq_and_redirect_scrub);

-#endif
-
#if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE)
#include <linux/jump_label.h>
#include <asm/string_64.h>
@@ -657,3 +655,4 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2fc0, quirk_intel_brickland_xeon_
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fc0, quirk_intel_brickland_xeon_ras_cap);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2083, quirk_intel_purley_xeon_ras_cap);
#endif
+#endif
diff --git a/arch/x86/kernel/unwind_guess.c b/arch/x86/kernel/unwind_guess.c
index 9298993dc8b7..2d721e533cf4 100644
--- a/arch/x86/kernel/unwind_guess.c
+++ b/arch/x86/kernel/unwind_guess.c
@@ -47,7 +47,14 @@ void __unwind_start(struct unwind_state *state, struct task_struct *task,
get_stack_info(first_frame, state->task, &state->stack_info,
&state->stack_mask);

- if (!__kernel_text_address(*first_frame))
+ /*
+ * The caller can provide the address of the first frame directly
+ * (first_frame) or indirectly (regs->sp) to indicate which stack frame
+ * to start unwinding at. Skip ahead until we reach it.
+ */
+ if (!unwind_done(state) &&
+ (!on_stack(&state->stack_info, first_frame, sizeof(long)) ||
+ !__kernel_text_address(*first_frame)))
unwind_next_frame(state);
}
EXPORT_SYMBOL_GPL(__unwind_start);