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| author | Tom Zanussi <zanussi@kernel.org> | 2020-01-14 13:50:16 -0600 |
|---|---|---|
| committer | Tom Zanussi <zanussi@kernel.org> | 2020-01-14 13:50:16 -0600 |
| commit | 2c99072340e97e3887fe81aa2628095524448ece (patch) | |
| tree | 24b39d2824607770fd43140dfc142a1713e1bf93 /arch/mips | |
| parent | 3bad60f64b7c60c842a38af913fc1dcaac2ab876 (diff) | |
| parent | b0cdffaa546e24acf92ab3b0d4e917a51aff6a82 (diff) | |
| download | linux-rt-2c99072340e97e3887fe81aa2628095524448ece.tar.gz | |
Merge tag 'v4.14.163' into v4.14-rt-work
This is the 4.14.163 stable release
Diffstat (limited to 'arch/mips')
| -rw-r--r-- | arch/mips/include/asm/thread_info.h | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h index 5e8927f99a76..a0338dbabeaa 100644 --- a/arch/mips/include/asm/thread_info.h +++ b/arch/mips/include/asm/thread_info.h @@ -52,8 +52,26 @@ struct thread_info { #define init_thread_info (init_thread_union.thread_info) #define init_stack (init_thread_union.stack) -/* How to get the thread information struct from C. */ +/* + * A pointer to the struct thread_info for the currently executing thread is + * held in register $28/$gp. + * + * We declare __current_thread_info as a global register variable rather than a + * local register variable within current_thread_info() because clang doesn't + * support explicit local register variables. + * + * When building the VDSO we take care not to declare the global register + * variable because this causes GCC to not preserve the value of $28/$gp in + * functions that change its value (which is common in the PIC VDSO when + * accessing the GOT). Since the VDSO shouldn't be accessing + * __current_thread_info anyway we declare it extern in order to cause a link + * failure if it's referenced. + */ +#ifdef __VDSO__ +extern struct thread_info *__current_thread_info; +#else register struct thread_info *__current_thread_info __asm__("$28"); +#endif static inline struct thread_info *current_thread_info(void) { |