4.9-stable patches

added patches:
	x86-asm-fix-inline-asm-call-constraints-for-gcc-4.4.patch

diff --git a/queue-4.9/series b/queue-4.9/series
index 17e456ade407018dff565bbf95cbb88b4ff12162..3d24d02235c76d0ff66dca96cca5fbce694e8206 100644 (file)
--- a/queue-4.9/series
+++ b/queue-4.9/series
@@ -36,3 +36,4 @@ tcp_bbr-fix-pacing_gain-to-always-be-unity-when-using-lt_bw.patch
 cls_u32-add-missing-rcu-annotation.patch
 ipv6-fix-so_reuseport-udp-socket-with-implicit-sk_ipv6only.patch
 soreuseport-fix-mem-leak-in-reuseport_add_sock.patch
+x86-asm-fix-inline-asm-call-constraints-for-gcc-4.4.patch

diff --git a/queue-4.9/x86-asm-fix-inline-asm-call-constraints-for-gcc-4.4.patch b/queue-4.9/x86-asm-fix-inline-asm-call-constraints-for-gcc-4.4.patch
new file mode 100644 (file)
index 0000000..e056a5f
--- /dev/null
+++ b/queue-4.9/x86-asm-fix-inline-asm-call-constraints-for-gcc-4.4.patch
@@ -0,0 +1,85 @@
+From 520a13c530aeb5f63e011d668c42db1af19ed349 Mon Sep 17 00:00:00 2001
+From: Josh Poimboeuf <jpoimboe@redhat.com>
+Date: Thu, 28 Sep 2017 16:58:26 -0500
+Subject: x86/asm: Fix inline asm call constraints for GCC 4.4
+
+From: Josh Poimboeuf <jpoimboe@redhat.com>
+
+commit 520a13c530aeb5f63e011d668c42db1af19ed349 upstream.
+
+The kernel test bot (run by Xiaolong Ye) reported that the following commit:
+
+  f5caf621ee35 ("x86/asm: Fix inline asm call constraints for Clang")
+
+is causing double faults in a kernel compiled with GCC 4.4.
+
+Linus subsequently diagnosed the crash pattern and the buggy commit and found that
+the issue is with this code:
+
+  register unsigned int __asm_call_sp asm("esp");
+  #define ASM_CALL_CONSTRAINT "+r" (__asm_call_sp)
+
+Even on a 64-bit kernel, it's using ESP instead of RSP.  That causes GCC
+to produce the following bogus code:
+
+  ffffffff8147461d:       89 e0                   mov    %esp,%eax
+  ffffffff8147461f:       4c 89 f7                mov    %r14,%rdi
+  ffffffff81474622:       4c 89 fe                mov    %r15,%rsi
+  ffffffff81474625:       ba 20 00 00 00          mov    $0x20,%edx
+  ffffffff8147462a:       89 c4                   mov    %eax,%esp
+  ffffffff8147462c:       e8 bf 52 05 00          callq  ffffffff814c98f0 <copy_user_generic_unrolled>
+
+Despite the absurdity of it backing up and restoring the stack pointer
+for no reason, the bug is actually the fact that it's only backing up
+and restoring the lower 32 bits of the stack pointer.  The upper 32 bits
+are getting cleared out, corrupting the stack pointer.
+
+So change the '__asm_call_sp' register variable to be associated with
+the actual full-size stack pointer.
+
+This also requires changing the __ASM_SEL() macro to be based on the
+actual compiled arch size, rather than the CONFIG value, because
+CONFIG_X86_64 compiles some files with '-m32' (e.g., realmode and vdso).
+Otherwise Clang fails to build the kernel because it complains about the
+use of a 64-bit register (RSP) in a 32-bit file.
+
+Reported-and-Bisected-and-Tested-by: kernel test robot <xiaolong.ye@intel.com>
+Diagnosed-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
+Cc: Alexander Potapenko <glider@google.com>
+Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
+Cc: Andy Lutomirski <luto@kernel.org>
+Cc: Arnd Bergmann <arnd@arndb.de>
+Cc: Dmitriy Vyukov <dvyukov@google.com>
+Cc: LKP <lkp@01.org>
+Cc: Linus Torvalds <torvalds@linux-foundation.org>
+Cc: Matthias Kaehlcke <mka@chromium.org>
+Cc: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>
+Cc: Peter Zijlstra <peterz@infradead.org>
+Cc: Thomas Gleixner <tglx@linutronix.de>
+Fixes: f5caf621ee35 ("x86/asm: Fix inline asm call constraints for Clang")
+Link: http://lkml.kernel.org/r/20170928215826.6sdpmwtkiydiytim@treble
+Signed-off-by: Ingo Molnar <mingo@kernel.org>
+Cc: Matthias Kaehlcke <mka@chromium.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ arch/x86/include/asm/asm.h |    4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+--- a/arch/x86/include/asm/asm.h
++++ b/arch/x86/include/asm/asm.h
+@@ -11,10 +11,12 @@
+ # define __ASM_FORM_COMMA(x) " " #x ","
+ #endif
+ 
+-#ifdef CONFIG_X86_32
++#ifndef __x86_64__
++/* 32 bit */
+ # define __ASM_SEL(a,b) __ASM_FORM(a)
+ # define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a)
+ #else
++/* 64 bit */
+ # define __ASM_SEL(a,b) __ASM_FORM(b)
+ # define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b)
+ #endif