diff options
| author | kib <kib@FreeBSD.org> | 2018-02-17 18:00:01 +0000 |
|---|---|---|
| committer | Luiz Souza <luiz@netgate.com> | 2018-02-19 14:55:29 -0300 |
| commit | 430a2bea3907149b30cc75fc722b6cf1f81da82a (patch) | |
| tree | c808db355a0220f39f7dff07a7e4805c57c44190 /sys/amd64/amd64/cpu_switch.S | |
| parent | 75492dc7653f9d5eb0e33bc8277957739f587ff0 (diff) | |
| download | FreeBSD-src-430a2bea3907149b30cc75fc722b6cf1f81da82a.zip FreeBSD-src-430a2bea3907149b30cc75fc722b6cf1f81da82a.tar.gz | |
MFC r328083,328096,328116,328119,328120,328128,328135,328153,328157,
328166,328177,328199,328202,328205,328468,328470,328624,328625,328627,
328628,329214,329297,329365:
Meltdown mitigation by PTI, PCID optimization of PTI, and kernel use of IBRS
for some mitigations of Spectre.
Tested by: emaste, Arshan Khanifar <arshankhanifar@gmail.com>
Discussed with: jkim
Sponsored by: The FreeBSD Foundation
(cherry picked from commit 6dd025b40ee6870bea6ba670f30dcf684edc3f6c)
Diffstat (limited to 'sys/amd64/amd64/cpu_switch.S')
| -rw-r--r-- | sys/amd64/amd64/cpu_switch.S | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/sys/amd64/amd64/cpu_switch.S b/sys/amd64/amd64/cpu_switch.S index 6e4ed35..75599a5 100644 --- a/sys/amd64/amd64/cpu_switch.S +++ b/sys/amd64/amd64/cpu_switch.S @@ -215,8 +215,10 @@ done_tss: movq %r8,PCPU(RSP0) movq %r8,PCPU(CURPCB) /* Update the TSS_RSP0 pointer for the next interrupt */ + cmpb $0,pti(%rip) + jne 1f movq %r8,TSS_RSP0(%rdx) - movq %r12,PCPU(CURTHREAD) /* into next thread */ +1: movq %r12,PCPU(CURTHREAD) /* into next thread */ /* Test if debug registers should be restored. */ testl $PCB_DBREGS,PCB_FLAGS(%r8) @@ -293,7 +295,12 @@ do_tss: movq %rdx,PCPU(TSSP) shrq $8,%rcx movl %ecx,8(%rax) movb $0x89,5(%rax) /* unset busy */ - movl $TSSSEL,%eax + cmpb $0,pti(%rip) + je 1f + movq PCPU(PRVSPACE),%rax + addq $PC_PTI_STACK+PC_PTI_STACK_SZ*8,%rax + movq %rax,TSS_RSP0(%rdx) +1: movl $TSSSEL,%eax ltr %ax jmp done_tss |
