include/linux/compiler.h: fix Oops for Clang-compiled kernels

GCC unescapes escaped string section names while Clang does not. Because
__section uses the `#` stringification operator for the section name, it
doesn't need to be escaped.

This fixes an Oops observed in distro's that use systemd and not
net.core.bpf_jit_enable=1, when their kernels are compiled with Clang.

Link: https://github.com/ClangBuiltLinux/linux/issues/619
Link: https://bugs.llvm.org/show_bug.cgi?id=42950
Link: https://marc.info/?l=linux-netdev&m=156412960619946&w=2
Link: https://lore.kernel.org/lkml/20190904181740.GA19688@gmail.com/
Acked-by: Will Deacon <will@kernel.org>
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
[Cherry-picked from the __section cleanup series for 5.3]
[Adjusted commit message]
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
This commit is contained in:
Nick Desaulniers 2019-08-28 15:55:23 -07:00 committed by Miguel Ojeda
parent 089cf7f6ec
commit bfafddd8de

View File

@ -24,7 +24,7 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
long ______r; \
static struct ftrace_likely_data \
__aligned(4) \
__section("_ftrace_annotated_branch") \
__section(_ftrace_annotated_branch) \
______f = { \
.data.func = __func__, \
.data.file = __FILE__, \
@ -60,7 +60,7 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
#define __trace_if_value(cond) ({ \
static struct ftrace_branch_data \
__aligned(4) \
__section("_ftrace_branch") \
__section(_ftrace_branch) \
__if_trace = { \
.func = __func__, \
.file = __FILE__, \
@ -118,7 +118,7 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
".popsection\n\t"
/* Annotate a C jump table to allow objtool to follow the code flow */
#define __annotate_jump_table __section(".rodata..c_jump_table")
#define __annotate_jump_table __section(.rodata..c_jump_table)
#else
#define annotate_reachable()
@ -298,7 +298,7 @@ unsigned long read_word_at_a_time(const void *addr)
* visible to the compiler.
*/
#define __ADDRESSABLE(sym) \
static void * __section(".discard.addressable") __used \
static void * __section(.discard.addressable) __used \
__PASTE(__addressable_##sym, __LINE__) = (void *)&sym;
/**