From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
Linus Torvalds <torvalds@linux-foundation.org>,
Steven Rostedt <rostedt@goodmis.org>
Subject: [PATCH 4.4 23/73] Makefile: Mute warning for __builtin_return_address(>0) for tracing only
Date: Wed, 28 Sep 2016 11:04:53 +0200 [thread overview]
Message-ID: <20160928090436.161137555@linuxfoundation.org> (raw)
In-Reply-To: <20160928090434.509091655@linuxfoundation.org>
4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Steven Rostedt <rostedt@goodmis.org>
commit 377ccbb483738f84400ddf5840c7dd8825716985 upstream.
With the latest gcc compilers, they give a warning if
__builtin_return_address() parameter is greater than 0. That is because if
it is used by a function called by a top level function (or in the case of
the kernel, by assembly), it can try to access stack frames outside the
stack and crash the system.
The tracing system uses __builtin_return_address() of up to 2! But it is
well aware of the dangers that it may have, and has even added precautions
to protect against it (see the thunk code in arch/x86/entry/thunk*.S)
Linus originally added KBUILD_CFLAGS that would suppress the warning for the
entire kernel, as simply adding KBUILD_CFLAGS to the tracing directory
wouldn't work. The tracing directory plays a bit with the CFLAGS and
requires a little more logic.
This adds that special logic to only suppress the warning for the tracing
directory. If it is used anywhere else outside of tracing, the warning will
still be triggered.
Link: http://lkml.kernel.org/r/20160728223043.51996267@grimm.local.home
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
Makefile | 1 -
kernel/trace/Makefile | 4 ++++
2 files changed, 4 insertions(+), 1 deletion(-)
--- a/Makefile
+++ b/Makefile
@@ -617,7 +617,6 @@ include arch/$(SRCARCH)/Makefile
KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
-KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
KBUILD_CFLAGS += -Os
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -1,4 +1,8 @@
+# We are fully aware of the dangers of __builtin_return_address()
+FRAME_CFLAGS := $(call cc-disable-warning,frame-address)
+KBUILD_CFLAGS += $(FRAME_CFLAGS)
+
# Do not instrument the tracer itself:
ifdef CONFIG_FUNCTION_TRACER
next prev parent reply other threads:[~2016-09-28 9:08 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20160928090623uscas1p1076bd85a3fd981ed5a1284f5bebb1bbf@uscas1p1.samsung.com>
2016-09-28 9:04 ` [PATCH 4.4 00/73] 4.4.23-stable review Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 01/73] include/linux/kernel.h: change abs() macro so it uses consistent return type Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 02/73] Fix build warning in kernel/cpuset.c Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 03/73] reiserfs: fix "new_insert_key may be used uninitialized ..." Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 09/73] crypto: arm64/aes-ctr - fix NULL dereference in tail processing Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 10/73] crypto: arm/aes-ctr " Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 11/73] crypto: skcipher - Fix blkcipher walk OOM crash Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 12/73] crypto: echainiv - Replace chaining with multiplication Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 13/73] ocfs2/dlm: fix race between convert and migration Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 14/73] ocfs2: fix start offset to ocfs2_zero_range_for_truncate() Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 15/73] kbuild: Do not run modules_install and install in paralel Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 16/73] Makefile: revert "Makefile: Document ability to make file.lst and file.S" partially Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 17/73] tools: Support relative directory path for O= Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 18/73] kbuild: forbid kernel directory to contain spaces and colons Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 19/73] Kbuild: disable maybe-uninitialized warning for CONFIG_PROFILE_ALL_BRANCHES Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 20/73] gcov: disable -Wmaybe-uninitialized warning Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 21/73] Disable "maybe-uninitialized" warning globally Greg Kroah-Hartman
2016-09-28 9:04 ` Greg Kroah-Hartman [this message]
2016-09-28 9:04 ` [PATCH 4.4 24/73] net: caif: fix misleading indentation Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 26/73] [media] am437x-vfpe: fix typo in vpfe_get_app_input_index Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 27/73] ath9k: fix misleading indentation Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 28/73] iwlegacy: avoid warning about missing braces Greg Kroah-Hartman
2016-09-28 9:04 ` [PATCH 4.4 29/73] Staging: iio: adc: fix indent on break statement Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 30/73] nouveau: fix nv40_perfctr_next() cleanup regression Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 31/73] megaraid: fix null pointer check in megasas_detach_one() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 32/73] bonding: Fix bonding crash Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 33/73] Revert "af_unix: Fix splice-bind deadlock" Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 34/73] af_unix: split u->readlock into two: iolock and bindlock Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 35/73] vti: flush x-netns xfrm cache when vti interface is removed Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 36/73] net/irda: handle iriap_register_lsap() allocation failure Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 37/73] tipc: fix NULL pointer dereference in shutdown() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 38/73] net/mlx5: Added missing check of msg length in verifying its signature Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 39/73] net: dsa: bcm_sf2: Fix race condition while unmasking interrupts Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 40/73] Revert "phy: IRQ cannot be shared" Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 41/73] net: smc91x: fix SMC accesses Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 42/73] bridge: re-introduce fix parsing of MLDv2 reports Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 43/73] pwm: Mark all devices as "might sleep" Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 44/73] autofs races Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 45/73] autofs: use dentry flags to block walks during expire Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 46/73] xfs: prevent dropping ioend completions during buftarg wait Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 47/73] fsnotify: add a way to stop queueing events on group shutdown Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 48/73] fanotify: fix list corruption in fanotify_get_response() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 49/73] fix fault_in_multipages_...() on architectures with no-op access_ok() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 50/73] mtd: maps: sa1100-flash: potential NULL dereference Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 51/73] mtd: pmcmsp-flash: Allocating too much in init_msp_flash() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 52/73] power: reset: hisi-reboot: Unmap region obtained by of_iomap Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 53/73] fix memory leaks in tracing_buffers_splice_read() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 54/73] tracing: Move mutex to protect against resetting of seq data Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 55/73] mm: delete unnecessary and unsafe init_tlb_ubc() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 56/73] can: flexcan: fix resume function Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 57/73] nl80211: validate number of probe response CSA counters Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 58/73] btrfs: ensure that file descriptor used with subvol ioctls is a dir Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 59/73] i2c-eg20t: fix race between i2c init and interrupt enable Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 60/73] i2c: qup: skip qup_i2c_suspend if the device is already runtime suspended Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 61/73] MIPS: Fix pre-r6 emulation FPU initialisation Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 63/73] MIPS: vDSO: Fix Malta EVA mapping to vDSO page structs Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 64/73] MIPS: Remove compact branch policy Kconfig entries Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 65/73] MIPS: Avoid a BUG warning during prctl(PR_SET_FP_MODE, ...) Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 66/73] MIPS: Add a missing ".set pop" in an early commit Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 67/73] MIPS: paravirt: Fix undefined reference to smp_bootstrap Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 68/73] PM / hibernate: Restore processor state before using per-CPU variables Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 69/73] PM / hibernate: Fix rtree_next_node() to avoid walking off list ends Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 70/73] power_supply: tps65217-charger: fix missing platform_set_drvdata() Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 71/73] power: supply: max17042_battery: fix model download bug Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 72/73] qxl: check for kmap failures Greg Kroah-Hartman
2016-09-28 9:05 ` [PATCH 4.4 73/73] hostfs: Freeing an ERR_PTR in hostfs_fill_sb_common() Greg Kroah-Hartman
2016-09-28 16:45 ` [PATCH 4.4 00/73] 4.4.23-stable review Shuah Khan
2016-09-28 22:43 ` Guenter Roeck
[not found] ` <57ec0f9e.07ddc20a.146f7.4be3@mx.google.com>
2016-09-29 9:01 ` Greg Kroah-Hartman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160928090436.161137555@linuxfoundation.org \
--to=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=rostedt@goodmis.org \
--cc=stable@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).