Merge tag 'kbuild-fixes-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- introduce __diag_* macros and suppress -Wattribute-alias warnings
from GCC 8
- fix stack protector test script for x86_64
- fix line number handling in Kconfig
- document that '#' starts a comment in Kconfig
- handle P_SYMBOL property in dump debugging of Kconfig
- correct help message of LD_DEAD_CODE_DATA_ELIMINATION
- fix occasional segmentation faults in Kconfig
* tag 'kbuild-fixes-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: loop boundary condition fix
kbuild: reword help of LD_DEAD_CODE_DATA_ELIMINATION
kconfig: handle P_SYMBOL in print_symbol()
kconfig: document Kconfig source file comments
kconfig: fix line numbers for if-entries in menu tree
stack-protector: Fix test with 32-bit userland and CONFIG_64BIT=y
powerpc: Remove -Wattribute-alias pragmas
disable -Wattribute-alias warning for SYSCALL_DEFINEx()
kbuild: add macro for controlling warnings to linux/compiler.h
diff --git a/Documentation/kbuild/kconfig-language.txt b/Documentation/kbuild/kconfig-language.txt
index 3534a84..64e0775 100644
--- a/Documentation/kbuild/kconfig-language.txt
+++ b/Documentation/kbuild/kconfig-language.txt
@@ -430,6 +430,12 @@
to use it. It should be placed at the top of the configuration, before any
other statement.
+'#' Kconfig source file comment:
+
+An unquoted '#' character anywhere in a source file line indicates
+the beginning of a source file comment. The remainder of that line
+is a comment.
+
Kconfig hints
-------------
diff --git a/arch/powerpc/kernel/pci_32.c b/arch/powerpc/kernel/pci_32.c
index 4f86105..d63b488 100644
--- a/arch/powerpc/kernel/pci_32.c
+++ b/arch/powerpc/kernel/pci_32.c
@@ -285,9 +285,6 @@
* Note that the returned IO or memory base is a physical address
*/
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wpragmas"
-#pragma GCC diagnostic ignored "-Wattribute-alias"
SYSCALL_DEFINE3(pciconfig_iobase, long, which,
unsigned long, bus, unsigned long, devfn)
{
@@ -313,4 +310,3 @@
return result;
}
-#pragma GCC diagnostic pop
diff --git a/arch/powerpc/kernel/pci_64.c b/arch/powerpc/kernel/pci_64.c
index 812171c..dff28f9 100644
--- a/arch/powerpc/kernel/pci_64.c
+++ b/arch/powerpc/kernel/pci_64.c
@@ -203,9 +203,6 @@
#define IOBASE_ISA_IO 3
#define IOBASE_ISA_MEM 4
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wpragmas"
-#pragma GCC diagnostic ignored "-Wattribute-alias"
SYSCALL_DEFINE3(pciconfig_iobase, long, which, unsigned long, in_bus,
unsigned long, in_devfn)
{
@@ -259,7 +256,6 @@
return -EOPNOTSUPP;
}
-#pragma GCC diagnostic pop
#ifdef CONFIG_NUMA
int pcibus_to_node(struct pci_bus *bus)
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index 7fb9f83..8afd146 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -1051,9 +1051,6 @@
}
/* We assume to be passed big endian arguments */
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wpragmas"
-#pragma GCC diagnostic ignored "-Wattribute-alias"
SYSCALL_DEFINE1(rtas, struct rtas_args __user *, uargs)
{
struct rtas_args args;
@@ -1140,7 +1137,6 @@
return 0;
}
-#pragma GCC diagnostic pop
/*
* Call early during boot, before mem init, to retrieve the RTAS
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 5eedbb2..e6474a4 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -1038,9 +1038,6 @@
}
#endif
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wpragmas"
-#pragma GCC diagnostic ignored "-Wattribute-alias"
#ifdef CONFIG_PPC64
COMPAT_SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
struct ucontext __user *, new_ctx, int, ctx_size)
@@ -1134,7 +1131,6 @@
set_thread_flag(TIF_RESTOREALL);
return 0;
}
-#pragma GCC diagnostic pop
#ifdef CONFIG_PPC64
COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
@@ -1231,9 +1227,6 @@
return 0;
}
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wpragmas"
-#pragma GCC diagnostic ignored "-Wattribute-alias"
#ifdef CONFIG_PPC32
SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
int, ndbg, struct sig_dbg_op __user *, dbg)
@@ -1337,7 +1330,6 @@
return 0;
}
#endif
-#pragma GCC diagnostic pop
/*
* OK, we're invoking a handler
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index d42b600..83d51bf 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -625,9 +625,6 @@
/*
* Handle {get,set,swap}_context operations
*/
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wpragmas"
-#pragma GCC diagnostic ignored "-Wattribute-alias"
SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
struct ucontext __user *, new_ctx, long, ctx_size)
{
@@ -693,7 +690,6 @@
set_thread_flag(TIF_RESTOREALL);
return 0;
}
-#pragma GCC diagnostic pop
/*
diff --git a/arch/powerpc/kernel/syscalls.c b/arch/powerpc/kernel/syscalls.c
index 083fa06..4662165 100644
--- a/arch/powerpc/kernel/syscalls.c
+++ b/arch/powerpc/kernel/syscalls.c
@@ -62,9 +62,6 @@
return ret;
}
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wpragmas"
-#pragma GCC diagnostic ignored "-Wattribute-alias"
SYSCALL_DEFINE6(mmap2, unsigned long, addr, size_t, len,
unsigned long, prot, unsigned long, flags,
unsigned long, fd, unsigned long, pgoff)
@@ -78,7 +75,6 @@
{
return do_mmap2(addr, len, prot, flags, fd, offset, PAGE_SHIFT);
}
-#pragma GCC diagnostic pop
#ifdef CONFIG_PPC32
/*
diff --git a/arch/powerpc/mm/subpage-prot.c b/arch/powerpc/mm/subpage-prot.c
index 75cb646..9d16ee2 100644
--- a/arch/powerpc/mm/subpage-prot.c
+++ b/arch/powerpc/mm/subpage-prot.c
@@ -186,9 +186,6 @@
* in a 2-bit field won't allow writes to a page that is otherwise
* write-protected.
*/
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wpragmas"
-#pragma GCC diagnostic ignored "-Wattribute-alias"
SYSCALL_DEFINE3(subpage_prot, unsigned long, addr,
unsigned long, len, u32 __user *, map)
{
@@ -272,4 +269,3 @@
up_write(&mm->mmap_sem);
return err;
}
-#pragma GCC diagnostic pop
diff --git a/include/linux/compat.h b/include/linux/compat.h
index b1a5562..c68acc4 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -72,6 +72,9 @@
*/
#ifndef COMPAT_SYSCALL_DEFINEx
#define COMPAT_SYSCALL_DEFINEx(x, name, ...) \
+ __diag_push(); \
+ __diag_ignore(GCC, 8, "-Wattribute-alias", \
+ "Type aliasing is used to sanitize syscall arguments");\
asmlinkage long compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)); \
asmlinkage long compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \
__attribute__((alias(__stringify(__se_compat_sys##name)))); \
@@ -80,8 +83,11 @@
asmlinkage long __se_compat_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
asmlinkage long __se_compat_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
{ \
- return __do_compat_sys##name(__MAP(x,__SC_DELOUSE,__VA_ARGS__));\
+ long ret = __do_compat_sys##name(__MAP(x,__SC_DELOUSE,__VA_ARGS__));\
+ __MAP(x,__SC_TEST,__VA_ARGS__); \
+ return ret; \
} \
+ __diag_pop(); \
static inline long __do_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
#endif /* COMPAT_SYSCALL_DEFINEx */
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index f1a7492..fd282c7 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -347,3 +347,28 @@
#if GCC_VERSION >= 50100
#define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
#endif
+
+/*
+ * Turn individual warnings and errors on and off locally, depending
+ * on version.
+ */
+#define __diag_GCC(version, severity, s) \
+ __diag_GCC_ ## version(__diag_GCC_ ## severity s)
+
+/* Severity used in pragma directives */
+#define __diag_GCC_ignore ignored
+#define __diag_GCC_warn warning
+#define __diag_GCC_error error
+
+/* Compilers before gcc-4.6 do not understand "#pragma GCC diagnostic push" */
+#if GCC_VERSION >= 40600
+#define __diag_str1(s) #s
+#define __diag_str(s) __diag_str1(s)
+#define __diag(s) _Pragma(__diag_str(GCC diagnostic s))
+#endif
+
+#if GCC_VERSION >= 80000
+#define __diag_GCC_8(s) __diag(s)
+#else
+#define __diag_GCC_8(s)
+#endif
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
index 6b79a9b..a8ba6b0 100644
--- a/include/linux/compiler_types.h
+++ b/include/linux/compiler_types.h
@@ -271,4 +271,22 @@
# define __native_word(t) (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long))
#endif
+#ifndef __diag
+#define __diag(string)
+#endif
+
+#ifndef __diag_GCC
+#define __diag_GCC(version, severity, string)
+#endif
+
+#define __diag_push() __diag(push)
+#define __diag_pop() __diag(pop)
+
+#define __diag_ignore(compiler, version, option, comment) \
+ __diag_ ## compiler(version, ignore, option)
+#define __diag_warn(compiler, version, option, comment) \
+ __diag_ ## compiler(version, warn, option)
+#define __diag_error(compiler, version, option, comment) \
+ __diag_ ## compiler(version, error, option)
+
#endif /* __LINUX_COMPILER_TYPES_H */
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 7381080..a368a68 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -231,6 +231,9 @@
*/
#ifndef __SYSCALL_DEFINEx
#define __SYSCALL_DEFINEx(x, name, ...) \
+ __diag_push(); \
+ __diag_ignore(GCC, 8, "-Wattribute-alias", \
+ "Type aliasing is used to sanitize syscall arguments");\
asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \
__attribute__((alias(__stringify(__se_sys##name)))); \
ALLOW_ERROR_INJECTION(sys##name, ERRNO); \
@@ -243,6 +246,7 @@
__PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__)); \
return ret; \
} \
+ __diag_pop(); \
static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
#endif /* __SYSCALL_DEFINEx */
diff --git a/init/Kconfig b/init/Kconfig
index fde3d09..041f3a0 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1051,10 +1051,9 @@
depends on HAVE_LD_DEAD_CODE_DATA_ELIMINATION
depends on EXPERT
help
- Select this if the architecture wants to do dead code and
- data elimination with the linker by compiling with
- -ffunction-sections -fdata-sections, and linking with
- --gc-sections.
+ Enable this if you want to do dead code and data elimination with
+ the linker by compiling with -ffunction-sections -fdata-sections,
+ and linking with --gc-sections.
This can reduce on disk and in-memory size of the kernel
code and static data, particularly for small configs and
diff --git a/scripts/gcc-x86_64-has-stack-protector.sh b/scripts/gcc-x86_64-has-stack-protector.sh
index 3755af0..75e4e22 100755
--- a/scripts/gcc-x86_64-has-stack-protector.sh
+++ b/scripts/gcc-x86_64-has-stack-protector.sh
@@ -1,4 +1,4 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
-echo "int foo(void) { char X[200]; return 3; }" | $* -S -x c -c -O0 -mcmodel=kernel -fno-PIE -fstack-protector - -o - 2> /dev/null | grep -q "%gs"
+echo "int foo(void) { char X[200]; return 3; }" | $* -S -x c -c -m64 -O0 -mcmodel=kernel -fno-PIE -fstack-protector - -o - 2> /dev/null | grep -q "%gs"
diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index 94a383b..f63b41b 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -171,6 +171,9 @@
* config BAZ
* int "BAZ Value"
* range 1..255
+ *
+ * Please, also check zconf.y:print_symbol() when modifying the
+ * list of property types!
*/
enum prop_type {
P_UNKNOWN,
diff --git a/scripts/kconfig/preprocess.c b/scripts/kconfig/preprocess.c
index 65da87f..5ca2df7 100644
--- a/scripts/kconfig/preprocess.c
+++ b/scripts/kconfig/preprocess.c
@@ -156,7 +156,7 @@
nread--;
/* remove trailing new lines */
- while (buf[nread - 1] == '\n')
+ while (nread > 0 && buf[nread - 1] == '\n')
nread--;
buf[nread] = 0;
diff --git a/scripts/kconfig/zconf.y b/scripts/kconfig/zconf.y
index 6f9b0aa..4b68272 100644
--- a/scripts/kconfig/zconf.y
+++ b/scripts/kconfig/zconf.y
@@ -31,7 +31,7 @@
static struct menu *current_menu, *current_entry;
%}
-%expect 32
+%expect 31
%union
{
@@ -337,7 +337,7 @@
/* if entry */
-if_entry: T_IF expr nl
+if_entry: T_IF expr T_EOL
{
printd(DEBUG_PARSE, "%s:%d:if\n", zconf_curname(), zconf_lineno());
menu_add_entry(NULL);
@@ -717,6 +717,10 @@
print_quoted_string(out, prop->text);
fputc('\n', out);
break;
+ case P_SYMBOL:
+ fputs( " symbol ", out);
+ fprintf(out, "%s\n", prop->sym->name);
+ break;
default:
fprintf(out, " unknown prop %d!\n", prop->type);
break;