[lkml]   [2020]   [Oct]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH v2 5/5] x86/head/64: Disable stack protection for head$(BITS).o
On 64-bit, the startup_64_setup_env() function added in
866b556efa12 ("x86/head/64: Install startup GDT")
has stack protection enabled because of set_bringup_idt_handler().

At this point, %gs is not yet initialized, and this doesn't cause a
crash only because the #PF handler from the decompressor stub is still
installed and handles the page fault.

Disable stack protection for the whole file, and do it on 32-bit as
well to avoid surprises.

Signed-off-by: Arvind Sankar <>
arch/x86/kernel/Makefile | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 04ceea8f4a89..68608bd892c0 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -47,6 +47,8 @@ endif
# non-deterministic coverage.

+CFLAGS_head$(BITS).o += -fno-stack-protector
CFLAGS_irq.o := -I $(srctree)/$(src)/../include/asm/trace

obj-y := process_$(BITS).o signal.o
 \ /
  Last update: 2020-10-08 21:17    [W:0.251 / U:3.548 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site