Mailing List Archive

commit b8c3e33a4fe4374f633b4369200731662ff1f750
Author: Jan Beulich <jbeulich@suse.com>
AuthorDate: Fri Aug 7 17:09:19 2020 +0200
Commit: Jan Beulich <jbeulich@suse.com>
CommitDate: Fri Aug 7 17:09:19 2020 +0200

x86/S3: put data segment registers into known state upon resume

wakeup_32 sets %ds and %es to BOOT_DS, while leaving %fs at what
wakeup_start did set it to, and %gs at whatever BIOS did load into it.
All of this may end up confusing the first load_segments() to run on
the BSP after resume, in particular allowing a non-nul selector value
to be left in %fs.

Alongside %ss, also put all other data segment registers into the same
state that the boot and CPU bringup paths put them in.

Reported-by: M. Vefa Bicakci <m.v.b@runbox.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 55f8c389d4348cc517946fdcb10794112458e81e
master date: 2020-07-24 10:17:26 +0200
---
xen/arch/x86/acpi/wakeup_prot.S | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/xen/arch/x86/acpi/wakeup_prot.S b/xen/arch/x86/acpi/wakeup_prot.S
index dcc7e2327d..a2c41c4f3f 100644
--- a/xen/arch/x86/acpi/wakeup_prot.S
+++ b/xen/arch/x86/acpi/wakeup_prot.S
@@ -49,6 +49,10 @@ ENTRY(s3_resume)
mov %rax, %cr0

mov $__HYPERVISOR_DS64, %eax
+ mov %eax, %ds
+ mov %eax, %es
+ mov %eax, %fs
+ mov %eax, %gs
mov %eax, %ss
mov saved_rsp(%rip), %rsp

--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.14