This is a note to let you know that I've just added the patch titled
x86/speculation: Fix up array_index_nospec_mask() asm constraint
to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: x86-speculation-fix-up-array_index_nospec_mask-asm-constraint.patch and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From be3233fbfcb8f5acb6e3bcd0895c3ef9e100d470 Mon Sep 17 00:00:00 2001
From: Dan Williams dan.j.williams@intel.com Date: Tue, 6 Feb 2018 18:22:40 -0800 Subject: x86/speculation: Fix up array_index_nospec_mask() asm constraint
From: Dan Williams dan.j.williams@intel.com
commit be3233fbfcb8f5acb6e3bcd0895c3ef9e100d470 upstream.
Allow the compiler to handle @size as an immediate value or memory directly rather than allocating a register.
Reported-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Dan Williams dan.j.williams@intel.com Cc: Andy Lutomirski luto@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Link: http://lkml.kernel.org/r/151797010204.1289.1510000292250184993.stgit@dwillia... Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/include/asm/barrier.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/include/asm/barrier.h +++ b/arch/x86/include/asm/barrier.h @@ -39,7 +39,7 @@ static inline unsigned long array_index_
asm ("cmp %1,%2; sbb %0,%0;" :"=r" (mask) - :"r"(size),"r" (index) + :"g"(size),"r" (index) :"cc"); return mask; }
Patches currently in stable-queue which might be from dan.j.williams@intel.com are
queue-4.9/nospec-move-array_index_nospec-parameter-checking-into-separate-macro.patch queue-4.9/x86-nvmx-properly-set-spec_ctrl-and-pred_cmd-before-merging-msrs.patch queue-4.9/x86-speculation-add-asm-msr-index.h-dependency.patch queue-4.9/x86-speculation-update-speculation-control-microcode-blacklist.patch queue-4.9/x86-speculation-correct-speculation-control-microcode-blacklist-again.patch queue-4.9/x86-speculation-fix-up-array_index_nospec_mask-asm-constraint.patch queue-4.9/kvm-x86-reduce-retpoline-performance-impact-in-slot_handle_level_range-by-always-inlining-iterator-helper-methods.patch queue-4.9/x86-speculation-clean-up-various-spectre-related-details.patch queue-4.9/x86-entry-64-compat-clear-registers-for-compat-syscalls-to-reduce-speculation-attack-surface.patch