lguest: use a special 1:1 linear pagetable mode until first switch.

The Host used to create some page tables for the Guest to use at the
top of Guest memory; it would then tell the Guest where this

lguest: use a special 1:1 linear pagetable mode until first switch.

The Host used to create some page tables for the Guest to use at the
top of Guest memory; it would then tell the Guest where this was. In
particular, it created linear mappings for 0 and 0xC0000000 addresses
because lguest used to switch to its real page tables quite late in
boot.

However, since d50d8fe19 Linux initialized boot page tables in
head_32.S even before the "are we lguest?" boot jump. So, now we can
simplify things: the Host pagetable code assumes 1:1 linear mapping
until it first calls the LHCALL_NEW_PGTABLE hypercall, which we now do
before we reach C code.

This also means that the Host doesn't need to know anything about the
Guest's PAGE_OFFSET. (Non-Linux guests might not even have such a
thing).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

show more ...

x86: Partly unify asm-offsets_{32,64}.c

Just consolidating the common parts. Full unification would seem
straight forward, but it's not clear the necessary #ifdef-s would
be acceptable.

Signed-off-

x86: Partly unify asm-offsets_{32,64}.c

Just consolidating the common parts. Full unification would seem
straight forward, but it's not clear the necessary #ifdef-s would
be acceptable.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <4D525D520200007800030EE9@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86, asm: Fix CFI macro invocations to deal with shortcomings in gas

gas prior to (perhaps) 2.16.90 has problems with passing non-
parenthesized expressions containing spaces to macros. Spaces, howe

x86, asm: Fix CFI macro invocations to deal with shortcomings in gas

gas prior to (perhaps) 2.16.90 has problems with passing non-
parenthesized expressions containing spaces to macros. Spaces, however,
get inserted by cpp between any macro expanding to a number and a
subsequent + or -. For the +, current x86 gas then removes the space
again (future gas may not do so), but for the - the space gets retained
and is then considered a separator between macro arguments.

Fix the respective definitions for both the - and + cases, so that they
neither contain spaces nor make cpp insert any (the latter by adding
seemingly redundant parentheses).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <4CBDBEBA020000780001E05A@vpn.id2.novell.com>
Cc: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

show more ...

lguest: optimize by coding restore_flags and irq_enable in assembler.

The downside of the last patch which made restore_flags and irq_enable
check interrupts is that they are now too big to be patch

lguest: optimize by coding restore_flags and irq_enable in assembler.

The downside of the last patch which made restore_flags and irq_enable
check interrupts is that they are now too big to be patched directly
into the callsites, so the C versions are always used.

But the C versions go via PV_CALLEE_SAVE_REGS_THUNK which saves all
the registers. In fact, we don't need any registers in the fast path,
so we can do better than this if we actually code them in assembler.

The results are in the noise, but since it's about the same amount of
code, it's worth applying.

1GB Guest->Host: input(suppressed),output(suppressed)
Before:
Seconds: 0:16.53
Packets: 377268,753673
Interrupts: 22461,24297
Notifications: 1(5245),21303(732370)
Net IRQs triggered: 377023(245),42578(711095)

After:
Seconds: 0:16.48
Packets: 377289,753673
Interrupts: 22281,24465
Notifications: 1(5245),21296(732377)
Net IRQs triggered: 377060(229),42564(711109)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

show more ...

x86, boot: make kernel_alignment adjustable; new bzImage fields

Make the kernel_alignment field adjustable; this allows us to set it
to a large value (intended to be 16 MB to avoid ZONE_DMA contenti

x86, boot: make kernel_alignment adjustable; new bzImage fields

Make the kernel_alignment field adjustable; this allows us to set it
to a large value (intended to be 16 MB to avoid ZONE_DMA contention,
memory holes and other weirdness) while a smart bootloader can still
force a loading at a lesser alignment if absolutely necessary.

Also export pref_address (preferred loading address, corresponding to
the link-time address) and init_size, the total amount of linear
memory the kernel will require during initialization.

[ Impact: allows better kernel placement, gives bootloader more info ]

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

show more ...

pm: rework includes, remove arch ifdefs

Make the following header file changes:

- remove arch ifdefs and asm/suspend.h from linux/suspend.h
- add asm/suspend.h to disk.c (for arch_prepare_suspend

pm: rework includes, remove arch ifdefs

Make the following header file changes:

- remove arch ifdefs and asm/suspend.h from linux/suspend.h
- add asm/suspend.h to disk.c (for arch_prepare_suspend())
- add linux/io.h to swsusp.c (for ioremap())
- x86 32/64 bit compile fixes

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Cc: Paul Mundt <lethal@linux-sh.org>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

x86: make lazy %gs optional on x86_32

Impact: pt_regs changed, lazy gs handling made optional, add slight
overhead to SAVE_ALL, simplifies error_code path a bit

On x86_32, %gs hasn't been u

x86: make lazy %gs optional on x86_32

Impact: pt_regs changed, lazy gs handling made optional, add slight
overhead to SAVE_ALL, simplifies error_code path a bit

On x86_32, %gs hasn't been used by kernel and handled lazily. pt_regs
doesn't have place for it and gs is saved/loaded only when necessary.
In preparation for stack protector support, this patch makes lazy %gs
handling optional by doing the followings.

* Add CONFIG_X86_32_LAZY_GS and place for gs in pt_regs.

* Save and restore %gs along with other registers in entry_32.S unless
LAZY_GS. Note that this unfortunately adds "pushl $0" on SAVE_ALL
even when LAZY_GS. However, it adds no overhead to common exit path
and simplifies entry path with error code.

* Define different user_gs accessors depending on LAZY_GS and add
lazy_save_gs() and lazy_load_gs() which are noop if !LAZY_GS. The
lazy_*_gs() ops are used to save, load and clear %gs lazily.

* Define ELF_CORE_COPY_KERNEL_REGS() which always read %gs directly.

xen and lguest changes need to be verified.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>

Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86: signal: move sigframe.h to arch/x86/include/asm

Impact: cleanup, move header file

Move arch/x86/kernel/sigframe.h to arch/x86/include/asm/sigframe.h.
It will be used in arch/x86/ia32/ia32_sign

x86: signal: move sigframe.h to arch/x86/include/asm

Impact: cleanup, move header file

Move arch/x86/kernel/sigframe.h to arch/x86/include/asm/sigframe.h.
It will be used in arch/x86/ia32/ia32_signal.c.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86/paravirt: split sysret and sysexit

Don't conflate sysret and sysexit; they're different instructions with
different semantics, and may be in use at the same time (at least
within the same kernel

x86/paravirt: split sysret and sysexit

Don't conflate sysret and sysexit; they're different instructions with
different semantics, and may be in use at the same time (at least
within the same kernel, depending on whether its an Intel or AMD
system).

sysexit - just return to userspace, does no register restoration of
any kind; must explicitly atomically enable interrupts.

sysret - reloads flags from r11, so no need to explicitly enable
interrupts on 64-bit, responsible for restoring usermode %gs

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citirx.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86: use kbuild.h

Drop the macro definitions in asm-offsets_*.c and use kbuild.h

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Ingo Molnar <mingo

x86: use kbuild.h

Drop the macro definitions in asm-offsets_*.c and use kbuild.h

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

x86: move struct definitions to unifed sigframe.h

[ tglx@linutronix.de: cleanup the other structs as well ]

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Roland McGrath <roland@red

x86: move struct definitions to unifed sigframe.h

[ tglx@linutronix.de: cleanup the other structs as well ]

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

show more ...

lguest: fix build breakage

[ mingo@elte.hu: merged to Rusty's patch ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

x86: fix lguest build failure

drivers/lguest/x86/switcher_32.S:(.text+0x3815f8):
undefined reference to `LGUEST_PAGES_regs_trapnum'

This problem was caused by asm-offsets.c only having the offset

x86: fix lguest build failure

drivers/lguest/x86/switcher_32.S:(.text+0x3815f8):
undefined reference to `LGUEST_PAGES_regs_trapnum'

This problem was caused by asm-offsets.c only having the offsets when
lguest *guest* support was set, not lguest host (host support used to
imply guest support, so now they're separate these bugs come out).

Lguest guest support and host support are separate config options:
they used to be tied together. Sort out which parts of asm-offsets are
needed for Guest and Host.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

show more ...

x86: unify struct desc_ptr

This patch unifies struct desc_ptr between i386 and x86_64.
They can be expressed in the exact same way in C code, only
having to change the name of one of them. As Xgt_de

x86: unify struct desc_ptr

This patch unifies struct desc_ptr between i386 and x86_64.
They can be expressed in the exact same way in C code, only
having to change the name of one of them. As Xgt_desc_struct
is ugly and big, this is the one that goes away.

There's also a padding field in i386, but it is not really
needed in the C structure definition.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

show more ...

x86: use generic register name in the thread and tss structures

This changes size-specific register names (eip/rip, esp/rsp, etc.) to
generic names in the thread and tss structures.

Signed-off-by:

x86: use generic register name in the thread and tss structures

This changes size-specific register names (eip/rip, esp/rsp, etc.) to
generic names in the thread and tss structures.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

show more ...

x86: use generic register names in struct sigcontext

Switch struct sigcontext (defined in <asm/sigcontext*.h>) to using
register names withut e- or r-prefixes for both 32- and 64-bit x86.
This is in

x86: use generic register names in struct sigcontext

Switch struct sigcontext (defined in <asm/sigcontext*.h>) to using
register names withut e- or r-prefixes for both 32- and 64-bit x86.
This is intended as a preliminary step in unifying this code between
architectures.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

show more ...

x86: rename the struct pt_regs members for 32/64-bit consistency

We have a lot of code which differs only by the naming of specific
members of structures that contain registers. In order to enable

x86: rename the struct pt_regs members for 32/64-bit consistency

We have a lot of code which differs only by the naming of specific
members of structures that contain registers. In order to enable
additional unifications, this patch drops the e- or r- size prefix
from the register names in struct pt_regs, and drops the x- prefixes
for segment registers on the 32-bit side.

This patch also performs the equivalent renames in some additional
places that might be candidates for unification in the future.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

show more ...

x86 vDSO: i386 vdso32

This makes the i386 kernel use the new vDSO build in arch/x86/vdso/vdso32/
to replace the old one from arch/x86/kernel/.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc:

x86 vDSO: i386 vdso32

This makes the i386 kernel use the new vDSO build in arch/x86/vdso/vdso32/
to replace the old one from arch/x86/kernel/.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

show more ...

x86 vDSO: harmonize asm-offsets

This change harmonizes the asm-offsets macros used in the 32-bit vDSO
across 32-bit and 64-bit builds. It's a purely cosmetic change for now,
but it paves the way fo

x86 vDSO: harmonize asm-offsets

This change harmonizes the asm-offsets macros used in the 32-bit vDSO
across 32-bit and 64-bit builds. It's a purely cosmetic change for now,
but it paves the way for consolidating the 32-bit vDSO builds.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

show more ...

x86: irqflags consolidation

This patch consolidates the irqflags include files containing common
paravirt definitions. The native definition for interrupt handling, halt,
and such, are the same for

x86: irqflags consolidation

This patch consolidates the irqflags include files containing common
paravirt definitions. The native definition for interrupt handling, halt,
and such, are the same for 32 and 64 bit, and they are kept in irqflags.h.
the differences are split in the arch-specific files.

The syscall function, irq_enable_sysexit, has a very specific i386 naming,
and its name is then changed to a more general one.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

show more ...

Boot with virtual == physical to get closer to native Linux.

1) This allows us to get alot closer to booting bzImages.

2) It means we don't have to know page_offset.

3) The Guest needs to modify t

Boot with virtual == physical to get closer to native Linux.

1) This allows us to get alot closer to booting bzImages.

2) It means we don't have to know page_offset.

3) The Guest needs to modify the boot pagetables to create the
PAGE_OFFSET mapping before jumping to C code.

4) guest_pa() walks the page tables rather than using page_offset.

5) We don't use page_offset to figure out whether to emulate: it was
always kinda quesationable, and won't work for instructions done
before remapping (bzImage unpacking in particular).

6) We still want the kernel address for tlb flushing: have the initial
hypercall give us that, too.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

show more ...

update boot spec to 2.07

Updates for version 2.07 of the boot protocol. This includes:

load_flags.KEEP_SEGMENTS- flag to request/inhibit segment reloads
hardware_subarch - what subarchitecture we'

update boot spec to 2.07

Updates for version 2.07 of the boot protocol. This includes:

load_flags.KEEP_SEGMENTS- flag to request/inhibit segment reloads
hardware_subarch - what subarchitecture we're booting under
hardware_subarch_data - per-architecture data

The intention of these changes is to make booting a paravirtualized
kernel work via the normal Linux boot protocol.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

paravirt: refactor struct paravirt_ops into smaller pv_*_ops

This patch refactors the paravirt_ops structure into groups of
functionally related ops:

pv_info - random info, rather than function ent

paravirt: refactor struct paravirt_ops into smaller pv_*_ops

This patch refactors the paravirt_ops structure into groups of
functionally related ops:

pv_info - random info, rather than function entrypoints
pv_init_ops - functions used at boot time (some for module_init too)
pv_misc_ops - lazy mode, which didn't fit well anywhere else
pv_time_ops - time-related functions
pv_cpu_ops - various privileged instruction ops
pv_irq_ops - operations for managing interrupt state
pv_apic_ops - APIC operations
pv_mmu_ops - operations for managing pagetables

There are several motivations for this:

1. Some of these ops will be general to all x86, and some will be
i386/x86-64 specific. This makes it easier to share common stuff
while allowing separate implementations where needed.

2. At the moment we must export all of paravirt_ops, but modules only
need selected parts of it. This allows us to export on a case by case
basis (and also choose which export license we want to apply).

3. Functional groupings make things a bit more readable.

Struct paravirt_ops is now only used as a template to generate
patch-site identifiers, and to extract function pointers for inserting
into jmp/calls when patching. It is only instantiated when needed.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Zach Amsden <zach@vmware.com>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Anthony Liguory <aliguori@us.ibm.com>
Cc: "Glauber de Oliveira Costa" <glommer@gmail.com>
Cc: Jun Nakajima <jun.nakajima@intel.com>

show more ...

i386: move kernel

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Merge tag 'x86-entry-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 entry code updates from Thomas Gleixner:

- Convert the 32bit syscalls to be pt_re

Merge tag 'x86-entry-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 entry code updates from Thomas Gleixner:

- Convert the 32bit syscalls to be pt_regs based which removes the
requirement to push all 6 potential arguments onto the stack and
consolidates the interface with the 64bit variant

- The first small portion of the exception and syscall related entry
code consolidation which aims to address the recently discovered
issues vs. RCU, int3, NMI and some other exceptions which can
interrupt any context. The bulk of the changes is still work in
progress and aimed for 5.8.

- A few lockdep namespace cleanups which have been applied into this
branch to keep the prerequisites for the ongoing work confined.

* tag 'x86-entry-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits)
x86/entry: Fix build error x86 with !CONFIG_POSIX_TIMERS
lockdep: Rename trace_{hard,soft}{irq_context,irqs_enabled}()
lockdep: Rename trace_softirqs_{on,off}()
lockdep: Rename trace_hardirq_{enter,exit}()
x86/entry: Rename ___preempt_schedule
x86: Remove unneeded includes
x86/entry: Drop asmlinkage from syscalls
x86/entry/32: Enable pt_regs based syscalls
x86/entry/32: Use IA32-specific wrappers for syscalls taking 64-bit arguments
x86/entry/32: Rename 32-bit specific syscalls
x86/entry/32: Clean up syscall_32.tbl
x86/entry: Remove ABI prefixes from functions in syscall tables
x86/entry/64: Add __SYSCALL_COMMON()
x86/entry: Remove syscall qualifier support
x86/entry/64: Remove ptregs qualifier from syscall table
x86/entry: Move max syscall number calculation to syscallhdr.sh
x86/entry/64: Split X32 syscall table into its own file
x86/entry/64: Move sys_ni_syscall stub to common.c
x86/entry/64: Use syscall wrappers for x32_rt_sigreturn
x86/entry: Refactor SYS_NI macros
...

show more ...