Srinivas Pandruvada reported a problem with system resume from
suspend-to-RAM on 32-bit x86 systems where the DS register of
the CPU is set to __KERNEL_DS instead of __USER_DS on return
to user space which cases a General Protection Fault to occur.
The issue is that DS is set to __KERNEL_DS by the ACPI resume code
path while the SYSEXIT path never reloads DS/ES. It assumes they
are still __USER_DS set at the SYSENTER time (Brian Gerst), so if
the return to user space happens to be through SYSEXIT, it will lead
to the reported GPF.
Fix the problem by setting the DS and ES registers to __USER_DS
as expected by the SYSEXIT path.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=61781
Link: http://marc.info/?l=linux-pm&m=143406648920385&w=2
Acked-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add an asmlinkage wrapper around acpi_enter_sleep_state() to prevent
an empty stub from being called by assmebly code for ACPI_REDUCED_HARDWARE
set.
As arch/x86/kernel/acpi/wakeup_xx.S is only compiled when CONFIG_ACPI=y
and there are no users of ACPI_HARDWARE_REDUCED, currently this is in
fact not a real issue, but a cleanup to reduce source code differences
between Linux and ACPICA upstream.
[rjw: Changelog]
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull x86 paravirt update from Ingo Molnar:
"Various paravirtualization related changes - the biggest one makes
guest support optional via CONFIG_HYPERVISOR_GUEST"
* 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, wakeup, sleep: Use pvops functions for changing GDT entries
x86, xen, gdt: Remove the pvops variant of store_gdt.
x86-32, gdt: Store/load GDT for ACPI S3 or hibernation/resume path is not needed
x86-64, gdt: Store/load GDT for ACPI S3 or hibernate/resume path is not needed.
x86: Make Linux guest support optional
x86, Kconfig: Move PARAVIRT_DEBUG into the paravirt menu
During the ACPI S3 suspend, we store the GDT in the wakup_header (see
wakeup_asm.s) field called 'pmode_gdt'.
Which is then used during the resume path and has the same exact
value as what the store/load_gdt do with the saved_context
(which is saved/restored via save/restore_processor_state()).
The flow during resume from ACPI S3 is simpler than the 64-bit
counterpart. We only use the early bootstrap once (wakeup_gdt) and
do various checks in real mode.
After the checks are completed, we load the saved GDT ('pmode_gdt') and
continue on with the resume (by heading to startup_32 in trampoline_32.S) -
which quickly jumps to what was saved in 'pmode_entry'
aka 'wakeup_pmode_return'.
The 'wakeup_pmode_return' restores the GDT (saved_gdt) again (which was
saved in do_suspend_lowlevel initially). After that it ends up calling
the 'ret_point' which calls 'restore_processor_state()'.
We have two opportunities to remove code where we restore the same GDT
twice.
Here is the call chain:
wakeup_start
|- lgdtl wakeup_gdt [the work-around broken BIOSes]
|
| - lgdtl pmode_gdt [the real one]
|
\-- startup_32 (in trampoline_32.S)
\-- wakeup_pmode_return (in wakeup_32.S)
|- lgdtl saved_gdt [the real one]
\-- ret_point
|..
|- call restore_processor_state
The hibernate path is much simpler. During the saving of the hibernation
image we call save_processor_state() and save the contents of that
along with the rest of the kernel in the hibernation image destination.
We save the EIP of 'restore_registers' (restore_jump_address) and
cr3 (restore_cr3).
During hibernate resume, the 'restore_registers' (via the
'restore_jump_address) in hibernate_asm_32.S is invoked which
restores the contents of most registers. Naturally the resume path benefits
from already being in 32-bit mode, so it does not have to reload the GDT.
It only reloads the cr3 (from restore_cr3) and continues on. Note
that the restoration of the restore image page-tables is done prior to
this.
After the 'restore_registers' it returns and we end up called
restore_processor_state() - where we reload the GDT. The reload of
the GDT is not needed as bootup kernel has already loaded the GDT
which is at the same physical location as the the restored kernel.
Note that the hibernation path assumes the GDT is correct during its
'restore_registers'. The assumption in the code is that the restored
image is the same as saved - meaning we are not trying to restore
an different kernel in the virtual address space of a new kernel.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/1365194544-14648-3-git-send-email-konrad.wilk@oracle.com
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Commit e44b7b7 ("x86: move suspend wakeup code to C") didn't
care to also eliminate the side effects that the earlier 4c49156
("x86: make arch/x86/kernel/acpi/wakeup_32.S use a separate")
had, thus leaving a now pointless, almost page size gap at the
beginning of .text.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Pavel Machek <pavel@ucw.cz>
Link: http://lkml.kernel.org/r/513DBAA402000078000C4896@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
cd74257b97
patched up GTS/BFS -- a feature we want to remove.
So revert it (by hand, due to conflict in sleep.h)
to prepare for GTS/BFS removal.
Signed-off-by: Len Brown <len.brown@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
With commit a2ef5c4fd4
"ACPI: Move module parameter gts and bfs to sleep.c" the
wake_sleep_flags is required when calling acpi_enter_sleep_state.
The assembler code in wakeup_*.S did not do that. One solution
is to call it from assembler and stick the wake_sleep_flags on
the stack (for 32-bit) or in %esi (for 64-bit). hpa and rafael
both suggested however to create a wrapper function to call
acpi_enter_sleep_state and call said wrapper function
("acpi_enter_s3") from assembler.
For 32-bit, the acpi_enter_s3 ends up looking as so:
push %ebp
mov %esp,%ebp
sub $0x8,%esp
movzbl 0xc1809314,%eax [wake_sleep_flags]
movl $0x3,(%esp)
mov %eax,0x4(%esp)
call 0xc12d1fa0 <acpi_enter_sleep_state>
leave
ret
And 64-bit:
movzbl 0x9afde1(%rip),%esi [wake_sleep_flags]
push %rbp
mov $0x3,%edi
mov %rsp,%rbp
callq 0xffffffff812e9800 <acpi_enter_sleep_state>
leaveq
retq
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Suggested-by: H. Peter Anvin <hpa@zytor.com>
[v2: Remove extra assembler operations, per hpa review]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/1335150198-21899-3-git-send-email-konrad.wilk@oracle.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
In general, the only definitions that assembly files can use
are in _types.S headers (where available), so convert them.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Move wakeup code to .c, so that video mode setting code can be shared
between boot and wakeup. Remove nasty assembly code in 64-bit case by
re-using trampoline code. Stack setup was fixed to clear high 16bits
of %esp, maybe that fixes some machines.
.c code sharing and morse code was done H. Peter Anvin, Sam Ravnborg
reviewed kbuild related stuff, and it seems okay to him. Rafael did
some cleanups.
[rjw:
* Made the patch stop breaking compilation on x86-32
* Added arch/x86/kernel/acpi/sleep.h
* Got rid of compiler warnings in arch/x86/kernel/acpi/sleep.c
* Fixed 32-bit compilation on x86-64 systems
* Added include/asm-x86/trampoline.h and fixed the non-SMP
compilation on 64-bit x86
* Removed arch/x86/kernel/acpi/sleep_32.c which was not used
* Fixed some breakage caused by the integration of smpboot.c done
under us in the meantime]
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
While examining vmlinux namelist on i386 (nm -v vmlinux) I noticed :
c01021d0 t es7000_rename_gsi
c010221a T es7000_start_cpu
<Big Hole>
c0103000 T thread_saved_pc
and
c0113218 T acpi_restore_state_mem
c0113219 T acpi_save_state_mem
<Big Hole>
c0114000 t wakeup_code
This is because arch/x86/kernel/acpi/wakeup_32.S forces a .text alignment
of 4096 bytes. (I have no idea if it is really needed, since
arch/x86/kernel/acpi/wakeup_64.S uses a 16 bytes alignment *only*)
So arch/x86/kernel/built-in.o also has this alignment
arch/x86/kernel/built-in.o: file format elf32-i386
Sections:
Idx Name Size VMA LMA File off Algn
0 .text 00018c94 00000000 00000000 00001000 2**12
CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
But as arch/x86/kernel/acpi/wakeup_32.o is not the first object linked
into arch/x86/kernel/built-in.o, linker had to build several holes to meet
alignement requirements, because of .o nestings in the kbuild process.
This can be solved by using a special section, .text.page_aligned, so that
no holes are needed.
# size vmlinux.before vmlinux.after
text data bss dec hex filename
4619942 422838 458752 5501532 53f25c vmlinux.before
4610534 422838 458752 5492124 53cd9c vmlinux.after
This saves 9408 bytes
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Old debugging hack sneaked back during x86 merge, this removes it.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
This removes old debugging stuff, that should be no longer neccessary. It
accessed VGA hardware (which may not be ready at this point), and used LEDs
at port 80 for debugging.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
