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| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2022-03-14 14:49:36 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-13 21:59:28 +0300 |
| commit | 68cea1e243b81e23e09b6822be6193321d9bf977 (patch) | |
| tree | 5b5e3217f1a2e1db10eb69ec12a3d093e1e0ae7c /kernel/Makefile | |
| parent | 429f413ed83f6b9f81e8c4362bcc19e817a4d208 (diff) | |
| download | linux-68cea1e243b81e23e09b6822be6193321d9bf977.tar.xz | |
static_call: Don't make __static_call_return0 static
commit 8fd4ddda2f49a66bf5dd3d0c01966c4b1971308b upstream.
System.map shows that vmlinux contains several instances of
__static_call_return0():
c0004fc0 t __static_call_return0
c0011518 t __static_call_return0
c00d8160 t __static_call_return0
arch_static_call_transform() uses the middle one to check whether we are
setting a call to __static_call_return0 or not:
c0011520 <arch_static_call_transform>:
c0011520: 3d 20 c0 01 lis r9,-16383 <== r9 = 0xc001 << 16
c0011524: 39 29 15 18 addi r9,r9,5400 <== r9 += 0x1518
c0011528: 7c 05 48 00 cmpw r5,r9 <== r9 has value 0xc0011518 here
So if static_call_update() is called with one of the other instances of
__static_call_return0(), arch_static_call_transform() won't recognise it.
In order to work properly, global single instance of __static_call_return0() is required.
Fixes: 3f2a8fc4b15d ("static_call/x86: Add __static_call_return0()")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/30821468a0e7d28251954b578e5051dc09300d04.1647258493.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/Makefile')
| -rw-r--r-- | kernel/Makefile | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index 4df609be42d0..0e119c52a2cd 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -113,7 +113,8 @@ obj-$(CONFIG_CPU_PM) += cpu_pm.o obj-$(CONFIG_BPF) += bpf/ obj-$(CONFIG_KCSAN) += kcsan/ obj-$(CONFIG_SHADOW_CALL_STACK) += scs.o -obj-$(CONFIG_HAVE_STATIC_CALL_INLINE) += static_call.o +obj-$(CONFIG_HAVE_STATIC_CALL) += static_call.o +obj-$(CONFIG_HAVE_STATIC_CALL_INLINE) += static_call_inline.o obj-$(CONFIG_CFI_CLANG) += cfi.o obj-$(CONFIG_PERF_EVENTS) += events/ |