commit 7292ae3d5a upstream.
The latest change of asm goto support check added passing of KBUILD_CFLAGS
to compiler. When these flags reference gcc plugins that are not built yet,
the check fails.
When one runs "make bzImage" followed by "make modules", the kernel is always
built with HAVE_JUMP_LABEL disabled, while the modules are built depending on
CONFIG_JUMP_LABEL. If HAVE_JUMP_LABEL macro happens to be different, modules
are built with undefined references, e.g.:
ERROR: "static_key_slow_inc" [net/netfilter/xt_TEE.ko] undefined!
ERROR: "static_key_slow_dec" [net/netfilter/xt_TEE.ko] undefined!
ERROR: "static_key_slow_dec" [net/netfilter/nft_meta.ko] undefined!
ERROR: "static_key_slow_inc" [net/netfilter/nft_meta.ko] undefined!
ERROR: "nf_hooks_needed" [net/netfilter/ipvs/ip_vs.ko] undefined!
ERROR: "nf_hooks_needed" [net/ipv6/ipv6.ko] undefined!
ERROR: "static_key_count" [net/ipv6/ipv6.ko] undefined!
ERROR: "static_key_slow_inc" [net/ipv6/ipv6.ko] undefined!
This change moves the check before all these references are added
to KBUILD_CFLAGS. This is correct because subsequent KBUILD_CFLAGS
modifications are not relevant to this check.
Reported-by: Anton V. Boyarshinov <boyarsh@altlinux.org>
Fixes: 35f860f9ba ("jump label: pass kbuild_cflags when checking for asm goto support")
Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: David Lin <dtwlin@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 35f860f9ba ]
Some versions of ARM GCC compiler such as Android toolchain throws in a
'-fpic' flag by default. This causes the gcc-goto check script to fail
although some config would have '-fno-pic' flag in the KBUILD_CFLAGS.
This patch passes the KBUILD_CFLAGS to the check script so that the
script does not rely on the default config from different compilers.
Link: http://lkml.kernel.org/r/20170120234329.78868-1-dtwlin@google.com
Signed-off-by: David Lin <dtwlin@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Michal Marek <mmarek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b334e19ae9 upstream.
In commit a76bcf557e ("Kbuild: enable -Wmaybe-uninitialized warning
for "make W=1""), I reverted another change that happened to fix a problem
with old compilers, and now we get this report again with old compilers
(prior to gcc-4.8) and GCOV enabled:
cc1: warnings being treated as errors
drivers/gpu/drm/i915/intel_ringbuffer.c: In function 'intel_ring_setup_status_page':
drivers/gpu/drm/i915/intel_ringbuffer.c:438: error: 'mmio.reg' may be used uninitialized in this function
At top level:
>> cc1: error: unrecognized command line option "-Wno-maybe-uninitialized"
The problem is that we turn off the warning conditionally in a number
of places as we should, but one of them does it unconditionally.
Instead, change it to call cc-disable-warning as we do elsewhere.
The original patch that caused it was merged into linux-4.7, then
4.8 removed the change and 4.9 brought it back, so we probably want
a backport to 4.9 once this is merged.
Use a ':=' assignment instead of '=' to force the cc-disable-warning
call to only be evaluated once instead of every time.
Fixes: a76bcf557e ("Kbuild: enable -Wmaybe-uninitialized warning for "make W=1"")
Fixes: e72e2dfe7c ("gcov: disable -Wmaybe-uninitialized warning")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When building a specific target such as bzImage, modules aren't normally
built. However if CONFIG_TRIM_UNUSED_KSYMS is enabled, no built modules
means none of the exported symbols are used and therefore they will all
be trimmed away from the final kernel. A subsequent "make modules" will
fail because modpost cannot find the needed symbols for those modules in
the kernel binary.
Let's make sure modules are also built whenever CONFIG_TRIM_UNUSED_KSYMS
is enabled and that the kernel binary is properly rebuilt accordingly.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some people are able to trigger a race where autoksyms.h is used before
its empty version is even created. Let's create it at the same time as
the directory holding it is created.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Tested-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull kbuild fixes from Michal Marek:
"Here are some regression fixes for kbuild:
- modversion support for exported asm symbols (Nick Piggin). The
affected architectures need separate patches adding
asm-prototypes.h.
- fix rebuilds of lib-ksyms.o (Nick Piggin)
- -fno-PIE builds (Sebastian Siewior and Borislav Petkov). This is
not a kernel regression, but one of the Debian gcc package.
Nevertheless, it's quite annoying, so I think it should go into
mainline and stable now"
* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
kbuild: Steal gcc's pie from the very beginning
kbuild: be more careful about matching preprocessed asm ___EXPORT_SYMBOL
x86/kexec: add -fno-PIE
scripts/has-stack-protector: add -fno-PIE
kbuild: add -fno-PIE
kbuild: modversions for EXPORT_SYMBOL() for asm
kbuild: prevent lib-ksyms.o rebuilds
So Sebastian turned off the PIE for kernel builds but that was too late
- Kbuild.include already uses KBUILD_CFLAGS and trying to disable gcc
options with, say cc-disable-warning, fails:
gcc -D__KERNEL__ -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs
...
-Wno-sign-compare -fno-asynchronous-unwind-tables -Wframe-address -c -x c /dev/null -o .31392.tmp
/dev/null:1:0: error: code model kernel does not support PIC mode
because that returns an error and we can't disable the warning. For
example in this case:
KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
which leads to gcc issuing all those warnings again.
So let's turn off PIE/PIC at the earliest possible moment, when we
declare KBUILD_CFLAGS so that cc-disable-warning picks it up too.
Also, we need the $(call cc-option ...) because -fno-PIE is supported
since gcc v3.4 and our lowest supported gcc version is 3.2 right now.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Michal Marek <mmarek@suse.com>