| Message ID | 20150614085735.GA22174@amd (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Sun, Jun 14, 2015 at 4:57 AM, Pavel Machek <pavel@ucw.cz> wrote: > On Sun 2015-06-14 09:49:22, Ingo Molnar wrote: >> >> * Linus Torvalds <torvalds@linux-foundation.org> wrote: >> >> > On Jun 13, 2015 8:56 PM, "Ingo Molnar" <mingo@kernel.org> wrote: >> > > >> > > Ok, so something like the patch below, right? >> > > >> > > movw $__KERNEL_DS, %ax >> > > movw %ax, %ss >> > > - movw %ax, %ds >> > > - movw %ax, %es >> > > movw %ax, %fs >> > > movw %ax, %gs >> > > >> > > + movw $__KERNEL_DS, %ax >> > > + movw %ax, %ds >> > > + movw %ax, %es >> > >> > .. except with less cut-and-paste bugs. >> > >> > That second KERNEL should be USER. >> >> Yeah, doh :-/ Updated patch below. > > Do we want similar patch for 64-bit, too? > > Signed-off-by: Pavel Machek <pavel@ucw.cz> > > diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S > index ae693b5..2ac2bc7 100644 > --- a/arch/x86/kernel/acpi/wakeup_64.S > +++ b/arch/x86/kernel/acpi/wakeup_64.S > @@ -18,10 +18,12 @@ ENTRY(wakeup_long64) > cmpq %rdx, %rax > jne bogus_64_magic > > - movw $__KERNEL_DS, %ax > - movw %ax, %ss > + movw $__USER_DS, %ax > movw %ax, %ds > movw %ax, %es > + > + movw $__KERNEL_DS, %ax > + movw %ax, %ss > movw %ax, %fs > movw %ax, %gs > movq saved_rsp, %rsp 64-bit is a different animal. DS/ES are ignored in 64-bit mode, so they are always userspace-owned, and only matter for 32-bit user processes. 64-bit does currently save/restore these in x86/power/cpu.c. -- Brian Gerst -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S index ae693b5..2ac2bc7 100644 --- a/arch/x86/kernel/acpi/wakeup_64.S +++ b/arch/x86/kernel/acpi/wakeup_64.S @@ -18,10 +18,12 @@ ENTRY(wakeup_long64) cmpq %rdx, %rax jne bogus_64_magic - movw $__KERNEL_DS, %ax - movw %ax, %ss + movw $__USER_DS, %ax movw %ax, %ds movw %ax, %es + + movw $__KERNEL_DS, %ax + movw %ax, %ss movw %ax, %fs movw %ax, %gs movq saved_rsp, %rsp