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| author | Chang S. Bae <chang.seok.bae@intel.com> | 2018-09-18 16:08:56 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-10-08 10:41:09 +0200 |
| commit | f4550b52e495e1b634d1f2c1004bcea5dc3321ea (patch) | |
| tree | de8e0d568f2f9df48fe87e2ecaccf4f28a18bb93 /arch/x86/kernel/process_64.c | |
| parent | 824eea38d239fb2a6027e65e18a5daef23019b00 (diff) | |
| download | linux-f4550b52e495e1b634d1f2c1004bcea5dc3321ea.tar.bz2 | |
x86/fsgsbase/64: Factor out FS/GS segment loading from __switch_to()
Instead of open coding the calls to load_seg_legacy(), introduce
x86_fsgsbase_load() to load FS/GS segments.
This makes it more explicit that this is part of FSGSBASE functionality,
and the new helper can be updated when FSGSBASE instructions are enabled.
[ mingo: Wrote new changelog. ]
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Markus T Metzger <markus.t.metzger@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Rik van Riel <riel@surriel.com>
Link: http://lkml.kernel.org/r/1537312139-5580-6-git-send-email-chang.seok.bae@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/process_64.c')
| -rw-r--r-- | arch/x86/kernel/process_64.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index e5fb0c3dee4d..d6674a425714 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -287,6 +287,15 @@ static __always_inline void load_seg_legacy(unsigned short prev_index, } } +static __always_inline void x86_fsgsbase_load(struct thread_struct *prev, + struct thread_struct *next) +{ + load_seg_legacy(prev->fsindex, prev->fsbase, + next->fsindex, next->fsbase, FS); + load_seg_legacy(prev->gsindex, prev->gsbase, + next->gsindex, next->gsbase, GS); +} + static unsigned long x86_fsgsbase_read_task(struct task_struct *task, unsigned short selector) { @@ -597,10 +606,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) if (unlikely(next->ds | prev->ds)) loadsegment(ds, next->ds); - load_seg_legacy(prev->fsindex, prev->fsbase, - next->fsindex, next->fsbase, FS); - load_seg_legacy(prev->gsindex, prev->gsbase, - next->gsindex, next->gsbase, GS); + x86_fsgsbase_load(prev, next); switch_fpu_finish(next_fpu, cpu); |