diff options
| author | Hugh Dickins <hughd@google.com> | 2018-02-13 16:45:20 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-02-17 13:21:12 +0100 |
| commit | 83946c33b9b99b5bc6157cfbf3970265f006c2bf (patch) | |
| tree | c4061e8d3558b0fbbd93e5d6186f2f1fbd4da8c5 /arch/x86/include/asm/vsyscall.h | |
| parent | 297c7cc4b5651b174a62925b6c961085f04979fd (diff) | |
kaiser: fix compile error without vsyscall
Tobias noticed a compile error on 4.4.115, and it's the same on 4.9.80:
arch/x86/mm/kaiser.c: In function ‘kaiser_init’:
arch/x86/mm/kaiser.c:348:8: error: ‘vsyscall_pgprot’ undeclared
(first use in this function)
It seems like his combination of kernel options doesn't work for KAISER.
X86_VSYSCALL_EMULATION is not set on his system, while LEGACY_VSYSCALL
is set to NONE (LEGACY_VSYSCALL_NONE=y). He managed to get things
compiling again, by moving the 'extern unsigned long vsyscall_pgprot'
outside of the preprocessor statement. This works because the optimizer
removes that code (vsyscall_enabled() is always false) - and that's how
it was done in some older backports.
Reported-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/include/asm/vsyscall.h')
| -rw-r--r-- | arch/x86/include/asm/vsyscall.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/include/asm/vsyscall.h b/arch/x86/include/asm/vsyscall.h index 9ee85066f407..62210da19a92 100644 --- a/arch/x86/include/asm/vsyscall.h +++ b/arch/x86/include/asm/vsyscall.h @@ -13,7 +13,6 @@ extern void map_vsyscall(void); */ extern bool emulate_vsyscall(struct pt_regs *regs, unsigned long address); extern bool vsyscall_enabled(void); -extern unsigned long vsyscall_pgprot; #else static inline void map_vsyscall(void) {} static inline bool emulate_vsyscall(struct pt_regs *regs, unsigned long address) @@ -22,5 +21,6 @@ static inline bool emulate_vsyscall(struct pt_regs *regs, unsigned long address) } static inline bool vsyscall_enabled(void) { return false; } #endif +extern unsigned long vsyscall_pgprot; #endif /* _ASM_X86_VSYSCALL_H */ |