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| author | Ahmad Fatoum <ahmad@a3f.at> | 2021-02-23 08:24:26 +0100 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2021-03-17 09:29:33 +0100 |
| commit | a1c1b4353c261d427b7a0d88ceccd61718f2031c (patch) | |
| tree | 4f97a350faa1d04fbf4c49297401ca2ddf101e18 /Makefile | |
| parent | 6e9d25d24629d5ea7675503625f6179b0ef6a9f6 (diff) | |
| download | barebox-a1c1b4353c261d427b7a0d88ceccd61718f2031c.tar.gz barebox-a1c1b4353c261d427b7a0d88ceccd61718f2031c.tar.xz | |
kbuild: add '-fno-stack-check' to barebox build options
This ports over Linux commit 3ce120b16cc5 ("kbuild: add
'-fno-stack-check' to kernel build options"):
Author: Linus Torvalds <torvalds@linux-foundation.org>
kbuild: add '-fno-stack-check' to kernel build options
It appears that hardened gentoo enables "-fstack-check" by default for
gcc.
That doesn't work _at_all_ for the kernel, because the kernel stack
doesn't act like a user stack at all: it's much smaller, and it doesn't
auto-expand on use. So the extra "probe one page below the stack" code
generated by -fstack-check just breaks the kernel in horrible ways,
causing infinite double faults etc.
[ I have to say, that the particular code gcc generates looks very
stupid even for user space where it works, but that's a separate
issue. ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I am porting it, because it may become more acute with the incoming
support for multiple stacks (via initjmp).
Signed-off-by: Ahmad Fatoum <ahmad@a3f.at>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'Makefile')
| -rw-r--r-- | Makefile | 3 |
1 files changed, 3 insertions, 0 deletions
@@ -630,6 +630,9 @@ KBUILD_CFLAGS += $(call cc-option, -fno-delete-null-pointer-checks,) # disable invalid "can't wrap" optimizations for signed / pointers KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow) +# Make sure -fstack-check isn't enabled (like gentoo apparently did) +KBUILD_CFLAGS += $(call cc-option,-fno-stack-check) + KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member) # Align the bit size of userspace programs with the kernel |