linux/arch
Sebastian Andrzej Siewior 1d731e731c x86/fpu: Add a fastpath to __fpu__restore_sig()
The previous commits refactor the restoration of the FPU registers so
that they can be loaded from in-kernel memory. This overhead can be
avoided if the load can be performed without a pagefault.

Attempt to restore FPU registers by invoking
copy_user_to_fpregs_zeroing(). If it fails try the slowpath which can
handle pagefaults.

 [ bp: Add a comment over the fastpath to be able to find one's way
   around the function. ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: kvm ML <kvm@vger.kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190403164156.19645-25-bigeasy@linutronix.de
2019-04-12 20:04:49 +02:00
..
alpha KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
arc KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
arm A collection of x86 and ARM bugfixes, and some improvements to documentation. 2019-03-31 08:55:59 -07:00
arm64 A collection of x86 and ARM bugfixes, and some improvements to documentation. 2019-03-31 08:55:59 -07:00
c6x KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
csky kbuild: force all architectures except um to include mandatory-y 2019-03-17 12:56:32 +09:00
h8300 KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
hexagon KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
ia64 KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
m68k KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
microblaze KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
mips A small batch of MIPS fixes for 5.1: 2019-03-19 10:50:15 -07:00
nds32 kbuild: force all architectures except um to include mandatory-y 2019-03-17 12:56:32 +09:00
nios2 KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
openrisc KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
parisc KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
powerpc powerpc fixes for 5.1 #4 2019-03-31 07:44:13 -07:00
riscv kbuild: force all architectures except um to include mandatory-y 2019-03-17 12:56:32 +09:00
s390 s390 update with improvements and bug fixes for 5.1-rc2 2019-03-28 08:35:32 -07:00
sh KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
sparc KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
um Merge branch 'for-linus-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2019-03-15 15:07:32 -07:00
unicore32 KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
x86 x86/fpu: Add a fastpath to __fpu__restore_sig() 2019-04-12 20:04:49 +02:00
xtensa KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported 2019-03-28 17:27:42 +01:00
.gitignore
Kconfig Char/Misc driver patches for 5.1-rc1 2019-03-06 14:18:59 -08:00