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Commit Graph

51 Commits

Author SHA1 Message Date
Brian Gerst
2cb16181a1 x86/boot: Simplify boot stack setup
Define the symbol __top_init_kernel_stack instead of duplicating
the offset from __end_init_task in multiple places.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20240321180506.89030-1-brgerst@gmail.com
2024-03-21 20:17:54 +01:00
Xin Li (Intel)
c416b5bac6 x86/fred: Fix init_task thread stack pointer initialization
As TOP_OF_KERNEL_STACK_PADDING was defined as 0 on x86_64, it went
unnoticed that the initialization of the .sp field in INIT_THREAD and some
calculations in the low level startup code do not take the padding into
account.

FRED enabled kernels require a 16 byte padding, which means that the init
task initialization and the low level startup code use the wrong stack
offset.

Subtract TOP_OF_KERNEL_STACK_PADDING in all affected places to adjust for
this.

Fixes: 65c9cc9e2c ("x86/fred: Reserve space for the FRED stack frame")
Fixes: 3adee777ad ("x86/smpboot: Remove initial_stack on 64-bit")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Closes: https://lore.kernel.org/oe-lkp/202402262159.183c2a37-lkp@intel.com
Link: https://lore.kernel.org/r/20240304083333.449322-1-xin@zytor.com
2024-03-07 11:55:36 +01:00
Jan Beulich
1cfd4ccb30 x86/Xen: tidy xen-head.S
First of all move PV-only ELF notes inside the XEN_PV conditional; note
that
- HV_START_LOW is dropped altogether, as it was meaningful for 32-bit PV
  only,
- the 32-bit instance of VIRT_BASE is dropped, as it would be dead code
  once inside the conditional,
- while PADDR_OFFSET is not exactly unused for PVH, it defaults to zero
  there, and the hypervisor (or tool stack) complains if it is present
  but VIRT_BASE isn't.
Then have the "supported features" note actually report reality: All
three of the features there are supported and/or applicable only in
certain cases.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/f99bacc6-2a2f-41b0-5c0b-e01b7051cb07@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2023-07-04 06:57:38 +02:00
Linus Torvalds
2aff7c706c Objtool changes for v6.4:
- Mark arch_cpu_idle_dead() __noreturn, make all architectures & drivers that did
    this inconsistently follow this new, common convention, and fix all the fallout
    that objtool can now detect statically.
 
  - Fix/improve the ORC unwinder becoming unreliable due to UNWIND_HINT_EMPTY ambiguity,
    split it into UNWIND_HINT_END_OF_STACK and UNWIND_HINT_UNDEFINED to resolve it.
 
  - Fix noinstr violations in the KCSAN code and the lkdtm/stackleak code.
 
  - Generate ORC data for __pfx code
 
  - Add more __noreturn annotations to various kernel startup/shutdown/panic functions.
 
  - Misc improvements & fixes.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'objtool-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Ingo Molnar:

 - Mark arch_cpu_idle_dead() __noreturn, make all architectures &
   drivers that did this inconsistently follow this new, common
   convention, and fix all the fallout that objtool can now detect
   statically

 - Fix/improve the ORC unwinder becoming unreliable due to
   UNWIND_HINT_EMPTY ambiguity, split it into UNWIND_HINT_END_OF_STACK
   and UNWIND_HINT_UNDEFINED to resolve it

 - Fix noinstr violations in the KCSAN code and the lkdtm/stackleak code

 - Generate ORC data for __pfx code

 - Add more __noreturn annotations to various kernel startup/shutdown
   and panic functions

 - Misc improvements & fixes

* tag 'objtool-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  x86/hyperv: Mark hv_ghcb_terminate() as noreturn
  scsi: message: fusion: Mark mpt_halt_firmware() __noreturn
  x86/cpu: Mark {hlt,resume}_play_dead() __noreturn
  btrfs: Mark btrfs_assertfail() __noreturn
  objtool: Include weak functions in global_noreturns check
  cpu: Mark nmi_panic_self_stop() __noreturn
  cpu: Mark panic_smp_self_stop() __noreturn
  arm64/cpu: Mark cpu_park_loop() and friends __noreturn
  x86/head: Mark *_start_kernel() __noreturn
  init: Mark start_kernel() __noreturn
  init: Mark [arch_call_]rest_init() __noreturn
  objtool: Generate ORC data for __pfx code
  x86/linkage: Fix padding for typed functions
  objtool: Separate prefix code from stack validation code
  objtool: Remove superfluous dead_end_function() check
  objtool: Add symbol iteration helpers
  objtool: Add WARN_INSN()
  scripts/objdump-func: Support multiple functions
  context_tracking: Fix KCSAN noinstr violation
  objtool: Add stackleak instrumentation to uaccess safe list
  ...
2023-04-28 14:02:54 -07:00
Josh Poimboeuf
fb799447ae x86,objtool: Split UNWIND_HINT_EMPTY in two
Mark reported that the ORC unwinder incorrectly marks an unwind as
reliable when the unwind terminates prematurely in the dark corners of
return_to_handler() due to lack of information about the next frame.

The problem is UNWIND_HINT_EMPTY is used in two different situations:

  1) The end of the kernel stack unwind before hitting user entry, boot
     code, or fork entry

  2) A blind spot in ORC coverage where the unwinder has to bail due to
     lack of information about the next frame

The ORC unwinder has no way to tell the difference between the two.
When it encounters an undefined stack state with 'end=1', it blindly
marks the stack reliable, which can break the livepatch consistency
model.

Fix it by splitting UNWIND_HINT_EMPTY into UNWIND_HINT_UNDEFINED and
UNWIND_HINT_END_OF_STACK.

Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/fd6212c8b450d3564b855e1cb48404d6277b4d9f.1677683419.git.jpoimboe@kernel.org
2023-03-23 23:18:58 +01:00
Brian Gerst
3adee777ad x86/smpboot: Remove initial_stack on 64-bit
In order to facilitate parallel startup, start to eliminate some of the
global variables passing information to CPUs in the startup path.

However, start by introducing one more: smpboot_control. For now this
merely holds the CPU# of the CPU which is coming up. Each CPU can then
find its own per-cpu data, and everything else it needs can be found
from there, allowing the other global variables to be removed.

First to be removed is initial_stack. Each CPU can load %rsp from its
current_task->thread.sp instead. That is already set up with the correct
idle thread for APs. Set up the .sp field in INIT_THREAD on x86 so that
the BSP also finds a suitable stack pointer in the static per-cpu data
when coming up on first boot.

On resume from S3, the CPU needs a temporary stack because its idle task
is already active. Instead of setting initial_stack, the sleep code can
simply set its own current->thread.sp to point to the temporary stack.
Nobody else cares about ->thread.sp for a thread which is currently on
a CPU, because the true value is actually in the %rsp register. Which
is restored with the rest of the CPU context in do_suspend_lowlevel().

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Usama Arif <usama.arif@bytedance.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Usama Arif <usama.arif@bytedance.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Link: https://lore.kernel.org/r/20230316222109.1940300-7-usama.arif@bytedance.com
2023-03-21 13:35:53 +01:00
Juergen Gross
336f560a89 x86/xen: don't let xen_pv_play_dead() return
A function called via the paravirt play_dead() hook should not return
to the caller.

xen_pv_play_dead() has a problem in this regard, as it currently will
return in case an offlined cpu is brought to life again. This can be
changed only by doing basically a longjmp() to cpu_bringup_and_idle(),
as the hypercall for bringing down the cpu will just return when the
cpu is coming up again. Just re-initializing the cpu isn't possible,
as the Xen hypervisor will deny that operation.

So introduce xen_cpu_bringup_again() resetting the stack and calling
cpu_bringup_and_idle(), which can be called after HYPERVISOR_vcpu_op()
in xen_pv_play_dead().

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221125063248.30256-2-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2023-02-13 06:53:19 +01:00
Linus Torvalds
ce114c8668 Just when you thought that all the speculation bugs were addressed and
solved and the nightmare is complete, here's the next one: speculating
 after RET instructions and leaking privileged information using the now
 pretty much classical covert channels.
 
 It is called RETBleed and the mitigation effort and controlling
 functionality has been modelled similar to what already existing
 mitigations provide.
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Merge tag 'x86_bugs_retbleed' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 retbleed fixes from Borislav Petkov:
 "Just when you thought that all the speculation bugs were addressed and
  solved and the nightmare is complete, here's the next one: speculating
  after RET instructions and leaking privileged information using the
  now pretty much classical covert channels.

  It is called RETBleed and the mitigation effort and controlling
  functionality has been modelled similar to what already existing
  mitigations provide"

* tag 'x86_bugs_retbleed' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  x86/speculation: Disable RRSBA behavior
  x86/kexec: Disable RET on kexec
  x86/bugs: Do not enable IBPB-on-entry when IBPB is not supported
  x86/entry: Move PUSH_AND_CLEAR_REGS() back into error_entry
  x86/bugs: Add Cannon lake to RETBleed affected CPU list
  x86/retbleed: Add fine grained Kconfig knobs
  x86/cpu/amd: Enumerate BTC_NO
  x86/common: Stamp out the stepping madness
  KVM: VMX: Prevent RSB underflow before vmenter
  x86/speculation: Fill RSB on vmexit for IBRS
  KVM: VMX: Fix IBRS handling after vmexit
  KVM: VMX: Prevent guest RSB poisoning attacks with eIBRS
  KVM: VMX: Convert launched argument to flags
  KVM: VMX: Flatten __vmx_vcpu_run()
  objtool: Re-add UNWIND_HINT_{SAVE_RESTORE}
  x86/speculation: Remove x86_spec_ctrl_mask
  x86/speculation: Use cached host SPEC_CTRL value for guest entry/exit
  x86/speculation: Fix SPEC_CTRL write on SMT state change
  x86/speculation: Fix firmware entry SPEC_CTRL handling
  x86/speculation: Fix RSB filling with CONFIG_RETPOLINE=n
  ...
2022-07-11 18:15:25 -07:00
Juergen Gross
96e8fc5818 x86/xen: Use clear_bss() for Xen PV guests
Instead of clearing the bss area in assembly code, use the clear_bss()
function.

This requires to pass the start_info address as parameter to
xen_start_kernel() in order to avoid the xen_start_info being zeroed
again.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20220630071441.28576-2-jgross@suse.com
2022-07-01 10:57:52 +02:00
Peter Zijlstra
9bb2ec608a objtool: Update Retpoline validation
Update retpoline validation with the new CONFIG_RETPOLINE requirement of
not having bare naked RET instructions.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-27 10:33:59 +02:00
Josh Poimboeuf
1ab80a0da4 x86/xen: Add ANNOTATE_NOENDBR to startup_xen()
The startup_xen() kernel entry point is referenced by the ".note.Xen"
section, and is the real entry point of the VM. Control transfer is
through IRET, which *could* set NEED_ENDBR, however Xen currently does
no such thing.

Add ANNOTATE_NOENDBR to silence future objtool warnings.

Fixes: ed53a0d971 ("x86/alternative: Use .ibt_endbr_seal to seal indirect calls")
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Link: https://lkml.kernel.org/r/a87bd48b06d11ec4b98122a429e71e489b4e48c3.1650300597.git.jpoimboe@redhat.com
2022-04-19 21:58:49 +02:00
Peter Zijlstra
5b2fc51576 x86/ibt,xen: Sprinkle the ENDBR
Even though Xen currently doesn't advertise IBT, prepare for when it
will eventually do so and sprinkle the ENDBR dust accordingly.

Even though most of the entry points are IRET like, the CPL0
Hypervisor can set WAIT-FOR-ENDBR and demand ENDBR at these sites.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.873919996@infradead.org
2022-03-15 10:32:35 +01:00
Peter Zijlstra
f94909ceb1 x86: Prepare asm files for straight-line-speculation
Replace all ret/retq instructions with RET in preparation of making
RET a macro. Since AS is case insensitive it's a big no-op without
RET defined.

  find arch/x86/ -name \*.S | while read file
  do
	sed -i 's/\<ret[q]*\>/RET/' $file
  done

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211204134907.905503893@infradead.org
2021-12-08 12:25:37 +01:00
Juergen Gross
eae446b765 x86/xen: remove 32-bit awareness from startup_xen
startup_xen is still 32-bit aware, even if no longer needed.

Replace the register macros by the 64-bit register names for making
it more readable.

Signed-off-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20211028081221.2475-5-jgross@suse.com
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-02 08:11:02 -05:00
Peter Zijlstra
74ea805b79 x86/xen: Make hypercall_page noinstr
vmlinux.o: warning: objtool: xen_set_debugreg()+0x3: call to hypercall_page() leaves .noinstr.text section
vmlinux.o: warning: objtool: xen_get_debugreg()+0x3: call to hypercall_page() leaves .noinstr.text section
vmlinux.o: warning: objtool: xen_irq_enable()+0x24: call to hypercall_page() leaves .noinstr.text section

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20210624095148.810950584@infradead.org
2021-09-17 13:14:44 +02:00
Josh Poimboeuf
b7b205c3a0 x86/xen: Move hypercall_page to top of the file
Because hypercall_page is page-aligned, the assembler inexplicably adds
an unreachable jump from after the end of the previous code to the
beginning of hypercall_page.

That confuses objtool, understandably.  It also creates significant text
fragmentation.  As a result, much of the object file is wasted text
(nops).

Move hypercall_page to the beginning of the file to both prevent the
text fragmentation and avoid the dead jump instruction.

$ size /tmp/head_64.before.o /tmp/head_64.after.o
   text	   data	    bss	    dec	    hex	filename
  10924	 307252	   4096	 322272	  4eae0	/tmp/head_64.before.o
   6823	 307252	   4096	 318171	  4dadb	/tmp/head_64.after.o

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20210820193107.omvshmsqbpxufzkc@treble
2021-09-15 15:51:44 +02:00
Josh Poimboeuf
f4b4bc10b0 x86/xen: Support objtool vmlinux.o validation in xen-head.S
The Xen hypercall page is filled with zeros, causing objtool to fall
through all the empty hypercall functions until it reaches a real
function, resulting in a stack state mismatch.

The build-time contents of the hypercall page don't matter because the
page gets rewritten by the hypervisor.  Make it more palatable to
objtool by making each hypervisor function a true empty function, with
nops and a return.

Cc: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/0883bde1d7a1fb3b6a4c952bc0200e873752f609.1611263462.git.jpoimboe@redhat.com
2021-01-26 11:33:02 -06:00
Juergen Gross
a13f2ef168 x86/xen: remove 32-bit Xen PV guest support
Xen is requiring 64-bit machines today and since Xen 4.14 it can be
built without 32-bit PV guest support. There is no need to carry the
burden of 32-bit PV guest support in the kernel any longer, as new
guests can be either HVM or PVH, or they can use a 64 bit kernel.

Remove the 32-bit Xen PV support from the kernel.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-08-11 08:26:48 +02:00
Juergen Gross
d6f34f4c6b x86/xen: fix booting 32-bit pv guest
Commit 2f62f36e62 ("x86/xen: Make the boot CPU idle task reliable")
introduced a regression for booting 32 bit Xen PV guests: the address
of the initial stack needs to be a virtual one.

Fixes: 2f62f36e62 ("x86/xen: Make the boot CPU idle task reliable")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20200409070001.16675-1-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-04-09 16:53:48 +02:00
Miroslav Benes
c3881eb58d x86/xen: Make the secondary CPU idle tasks reliable
The unwinder reports the secondary CPU idle tasks' stack on XEN PV as
unreliable, which affects at least live patching.
cpu_initialize_context() sets up the context of the CPU through
VCPUOP_initialise hypercall. After it is woken up, the idle task starts
in cpu_bringup_and_idle() function and its stack starts at the offset
right below pt_regs. The unwinder correctly detects the end of stack
there but it is confused by NULL return address in the last frame.

Introduce a wrapper in assembly, which just calls
cpu_bringup_and_idle(). The return address is thus pushed on the stack
and the wrapper contains the annotation hint for the unwinder regarding
the stack state.

Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-03-30 17:32:10 +02:00
Miroslav Benes
2f62f36e62 x86/xen: Make the boot CPU idle task reliable
The unwinder reports the boot CPU idle task's stack on XEN PV as
unreliable, which affects at least live patching. There are two reasons
for this. First, the task does not follow the x86 convention that its
stack starts at the offset right below saved pt_regs. It allows the
unwinder to easily detect the end of the stack and verify it. Second,
startup_xen() function does not store the return address before jumping
to xen_start_kernel() which confuses the unwinder.

Amend both issues by moving the starting point of initial stack in
startup_xen() and storing the return address before the jump, which is
exactly what call instruction does.

Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-03-30 17:32:04 +02:00
Jiri Slaby
bc7b11c04e x86/asm/64: Change all ENTRY+END to SYM_CODE_*
Change all assembly code which is marked using END (and not ENDPROC).
Switch all these to the appropriate new annotation SYM_CODE_START and
SYM_CODE_END.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> [xen bits]
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Cao jin <caoj.fnst@cn.fujitsu.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: linux-arch@vger.kernel.org
Cc: Maran Wilson <maran.wilson@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20191011115108.12392-24-jslaby@suse.cz
2019-10-18 11:58:26 +02:00
Andy Lutomirski
e6401c1309 x86/irq/64: Split the IRQ stack into its own pages
Currently, the IRQ stack is hardcoded as the first page of the percpu
area, and the stack canary lives on the IRQ stack. The former gets in
the way of adding an IRQ stack guard page, and the latter is a potential
weakness in the stack canary mechanism.

Split the IRQ stack into its own private percpu pages.

[ tglx: Make 64 and 32 bit share struct irq_stack ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Feng Tang <feng.tang@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jordan Borgner <mail@jordan-borgner.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Maran Wilson <maran.wilson@oracle.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: "Rafael Ávila de Espíndola" <rafael@espindo.la>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: x86-ml <x86@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20190414160146.267376656@linutronix.de
2019-04-17 15:37:02 +02:00
Boris Ostrovsky
a5a18ae73b xen/pvh: Indicate XENFEAT_linux_rsdp_unrestricted to Xen
Pre-4.17 kernels ignored start_info's rsdp_paddr pointer and instead
relied on finding RSDP in standard location in BIOS RO memory. This
has worked since that's where Xen used to place it.

However, with recent Xen change (commit 4a5733771e6f ("libxl: put RSDP
for PVH guest near 4GB")) it prefers to keep RSDP at a "non-standard"
address. Even though as of commit b17d9d1df3 ("x86/xen: Add pvh
specific rsdp address retrieval function") Linux is able to find RSDP,
for back-compatibility reasons we need to indicate to Xen that we can
handle this, an we do so by setting XENFEAT_linux_rsdp_unrestricted
flag in ELF notes.

(Also take this opportunity and sync features.h header file with Xen)

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
2018-04-10 09:22:22 -04:00
Juergen Gross
4f277295e5 x86/xen: init %gs very early to avoid page faults with stack protector
When running as Xen pv guest %gs is initialized some time after
C code is started. Depending on stack protector usage this might be
too late, resulting in page faults.

So setup %gs and MSR_GS_BASE in assembly code already.

Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: Chris Patterson <cjp256@gmail.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2018-02-06 09:37:18 +01:00
Ingo Molnar
b3d9a13681 Merge branch 'linus' into x86/asm, to pick up fixes and resolve conflicts
Conflicts:
	arch/x86/kernel/cpu/Makefile

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 10:53:06 +01:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Josh Poimboeuf
abbe1cac62 x86/xen: Add unwind hint annotations
Add unwind hint annotations to the xen head code so the ORC unwinder can
read head_64.o.

hypercall_page needs empty annotations at 32-byte intervals to match the
'xen_hypercall_*' ELF functions at those locations.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/70ed2eb516fe9266be766d953f93c2571bca88cc.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-28 09:39:03 +02:00
Josh Poimboeuf
2582d3df95 x86/xen: Fix xen head ELF annotations
Mark the ends of the startup_xen and hypercall_page code sections.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/3a80a394d30af43d9cefa1a29628c45ed8420c97.1505764066.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-28 09:39:03 +02:00
Kirill A. Shutemov
daaa42f041 x86/xen: Redefine XEN_ELFNOTE_INIT_P2M using PUD_SIZE * PTRS_PER_PUD
XEN_ELFNOTE_INIT_P2M has to be 512GB for both 4- and 5-level paging.
(PUD_SIZE * PTRS_PER_PUD) would do this.

Unfortunately, we cannot use P4D_SIZE, which would fit here. With
current headers structure it cannot be used in assembly, if p4d
level is folded.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170716225954.74185-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-21 10:05:18 +02:00
Vitaly Kuznetsov
c504b2f106 x86/xen: define startup_xen for XEN PV only
startup_xen references PV-only code, decorate it with #ifdef CONFIG_XEN_PV
to make PV-free builds possible.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2017-05-02 11:09:37 +02:00
Boris Ostrovsky
063334f305 xen/x86: Remove PVH support
We are replacing existing PVH guests with new implementation.

We are keeping xen_pvh_domain() macro (for now set to zero) because
when we introduce new PVH implementation later in this series we will
reuse current PVH-specific code (xen_pvh_gnttab_setup()), and that
code is conditioned by 'if (xen_pvh_domain())'. (We will also need
a noop xen_pvh_domain() for !CONFIG_XEN_PVH).

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2017-02-07 08:07:01 -05:00
Linus Torvalds
d88f48e128 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - fix hotplug bugs
   - fix irq live lock
   - fix various topology handling bugs
   - fix APIC ACK ordering
   - fix PV iopl handling
   - fix speling
   - fix/tweak memcpy_mcsafe() return value
   - fix fbcon bug
   - remove stray prototypes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/msr: Remove unused native_read_tscp()
  x86/apic: Remove declaration of unused hw_nmi_is_cpu_stuck
  x86/oprofile/nmi: Add missing hotplug FROZEN handling
  x86/hpet: Use proper mask to modify hotplug action
  x86/apic/uv: Fix the hotplug notifier
  x86/apb/timer: Use proper mask to modify hotplug action
  x86/topology: Use total_cpus not nr_cpu_ids for logical packages
  x86/topology: Fix Intel HT disable
  x86/topology: Fix logical package mapping
  x86/irq: Cure live lock in fixup_irqs()
  x86/tsc: Prevent NULL pointer deref in calibrate_delay_is_known()
  x86/apic: Fix suspicious RCU usage in smp_trace_call_function_interrupt()
  x86/iopl: Fix iopl capability check on Xen PV
  x86/iopl/64: Properly context-switch IOPL on Xen PV
  selftests/x86: Add an iopl test
  x86/mm, x86/mce: Fix return type/value for memcpy_mcsafe()
  x86/video: Don't assume all FB devices are PCI devices
  arch/x86/irq: Purge useless handler declarations from hw_irq.h
  x86: Fix misspellings in comments
2016-03-24 09:47:32 -07:00
Boris Ostrovsky
4478c407ea xen/x86: Drop mode-selecting ifdefs in startup_xen()
Use asm/asm.h macros instead.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-03-03 16:20:22 +00:00
Boris Ostrovsky
04b6b4a568 xen/x86: Zero out .bss for PV guests
ELF spec is unclear about whether .bss must me cleared by the loader.
Currently the domain builder does it when loading the guest but because
it is not (or rather may not be) guaranteed we should zero it out
explicitly.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-03-03 16:20:09 +00:00
Adam Buchbinder
6a6256f9e0 x86: Fix misspellings in comments
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: trivial@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-24 08:44:58 +01:00
Juergen Gross
8f5b0c6398 xen: eliminate scalability issues from initial mapping setup
Direct Xen to place the initial P->M table outside of the initial
mapping, as otherwise the 1G (implementation) / 2G (theoretical)
restriction on the size of the initial mapping limits the amount
of memory a domain can be handed initially.

As the initial P->M table is copied rather early during boot to
domain private memory and it's initial virtual mapping is dropped,
the easiest way to avoid virtual address conflicts with other
addresses in the kernel is to use a user address area for the
virtual address of the initial P->M table. This allows us to just
throw away the page tables of the initial mapping after the copy
without having to care about address invalidation.

It should be noted that this patch won't enable a pv-domain to USE
more than 512 GB of RAM. It just enables it to be started with a
P->M table covering more memory. This is especially important for
being able to boot a Dom0 on a system with more than 512 GB memory.

Signed-off-by: Juergen Gross <jgross@suse.com>
Based-on-patch-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-08-20 12:24:18 +01:00
Juergen Gross
526abeaed4 xen: use generated hypercall symbols in arch/x86/xen/xen-head.S
Instead of manually list each hypercall in arch/x86/xen/xen-head.S
use the auto generated symbol list.

This also corrects the wrong address of xen_hypercall_mca which was
located 32 bytes higher than it should.

Symbol addresses have been verified to match the correct ones via
objdump output.

Based-on-patch-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-03-16 14:49:14 +00:00
Mukesh Rathor
a2ef5dc2c7 x86/xen: Set EFER.NX and EFER.SCE in PVH guests
This fixes two bugs in PVH guests:

  - Not setting EFER.NX means the NX bit in page table entries is
    ignored on Intel processors and causes reserved bit page faults on
    AMD processors.

  - After the Xen commit 7645640d6ff1 ("x86/PVH: don't set EFER_SCE for
    pvh guest") PVH guests are required to set EFER.SCE to enable the
    SYSCALL instruction.

Secondary VCPUs are started with pagetables with the NX bit set so
EFER.NX must be set before using any stack or data segment.
xen_pvh_cpu_early_init() is the new secondary VCPU entry point that
sets EFER before jumping to cpu_bringup_and_idle().

Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-06 10:27:47 +01:00
Juergen Gross
d1e9abd630 xen: eliminate scalability issues from initrd handling
Size restrictions native kernels wouldn't have resulted from the initrd
getting mapped into the initial mapping. The kernel doesn't really need
the initrd to be mapped, so use infrastructure available in Xen to avoid
the mapping and hence the restriction.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-03 12:34:52 +01:00
Mukesh Rathor
4e903a20da xen/pvh: Support ParaVirtualized Hardware extensions (v3).
PVH allows PV linux guest to utilize hardware extended capabilities,
such as running MMU updates in a HVM container.

The Xen side defines PVH as (from docs/misc/pvh-readme.txt,
with modifications):

"* the guest uses auto translate:
 - p2m is managed by Xen
 - pagetables are owned by the guest
 - mmu_update hypercall not available
* it uses event callback and not vlapic emulation,
* IDT is native, so set_trap_table hcall is also N/A for a PVH guest.

For a full list of hcalls supported for PVH, see pvh_hypercall64_table
in arch/x86/hvm/hvm.c in xen.  From the ABI prespective, it's mostly a
PV guest with auto translate, although it does use hvm_op for setting
callback vector."

Use .ascii and .asciz to define xen feature string. Note, the PVH
string must be in a single line (not multiple lines with \) to keep the
assembler from putting null char after each string before \.
This patch allows it to be configured and enabled.

We also use introduce the 'XEN_ELFNOTE_SUPPORTED_FEATURES' ELF note to
tell the hypervisor that 'hvm_callback_vector' is what the kernel
needs. We can not put it in 'XEN_ELFNOTE_FEATURES' as older hypervisor
parse fields they don't understand as errors and refuse to load
the kernel. This work-around fixes the problem.

Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-01-06 10:44:24 -05:00
Konrad Rzeszutek Wilk
7d0642b937 xen/perf: Define .glob for the different hypercalls.
This allows us in perf to have this:

 99.67%  [kernel]             [k] xen_hypercall_sched_op
  0.11%  [kernel]             [k] xen_hypercall_xen_version

instead of the borring ever-encompassing:

 99.13%  [kernel]              [k] hypercall_page

[v2: Use a macro to define the name and skip]
[v3: Use balign per Jan's suggestion]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-30 14:27:48 -04:00
Stratos Psomadakis
7bf04be8f4 x86, asm: Cleanup unnecssary macros in asm-offsets.c
PAGE_SIZE_asm, PAGE_SHIFT_asm, THREAD_SIZE_asm can be safely removed from 
asm-offsets.c, and be replaced by their non-'_asm' counterparts in the code 
that uses them, since the _AC macro defined in include/linux/const.h makes
PAGE_SIZE/PAGE_SHIFT/THREAD_SIZE work with as.

Signed-off-by: Stratos Psomadakis <psomas@cslab.ece.ntua.gr>
LKML-Reference: <1298666774-17646-2-git-send-email-psomas@cslab.ece.ntua.gr>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2011-02-25 16:37:32 -08:00
Jeremy Fitzhardinge
0341c14da4 x86: use _types.h headers in asm where available
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>
2009-02-13 11:35:01 -08:00
Jeremy Fitzhardinge
8c5e5ac32f xen64: add xen-head code to head_64.S
Add the Xen entrypoint and ELF notes to head_64.S.  Adapts xen-head.S
to compile either 32-bit or 64-bit.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.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>
2008-07-16 10:58:41 +02:00
Jeremy Fitzhardinge
7077c33d81 xen: make ELF notes work for 32 and 64 bit
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.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>
2008-07-16 10:56:32 +02:00
Jeremy Fitzhardinge
a987b16cc6 xen: don't drop NX bit
Because NX is now enforced properly, we must put the hypercall page
into the .text segment so that it is executable.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Cc: the arch/x86 maintainers <x86@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-20 14:55:13 +02:00
Jeremy Fitzhardinge
7e0edc1bc3 xen: add new Xen elfnote types and use them appropriately
Define recently added XEN_ELFNOTEs, and use them appropriately.
Most significantly, this enables domain checkpointing (xm save -c).

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-02 13:25:51 +02:00
Jeremy Fitzhardinge
3843fc2575 xen: remove support for non-PAE 32-bit
Non-PAE operation has been deprecated in Xen for a while, and is
rarely tested or used.  xen-unstable has now officially dropped
non-PAE support.  Since Xen/pvops' non-PAE support has also been
broken for a while, we may as well completely drop it altogether.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-22 18:42:49 +02:00
Sam Ravnborg
08b6d290f9 xen: fix section usage in xen-head.S and setup.c
additional section for .init.text appending a number.

A side effect of this was a section mismatch warning because modpost did
not recognize a .init.text section named .init.text.1: WARNING:
vmlinux.o(.text.head+0x247): Section mismatch: reference to
.init.text.1:start_kernel (between 'is386' and 'check_x87')

Fix this by hardcoding the "ax" in the pushsection.  Thanks to Torlaf for
reporting this.

Alan Modra provided the hint that made me able to locate the root cause of
this warning.  And Mike Frysinger told me how to properly fix it using
__INIT/__FINIT.

Fix following Section mismatch warning in addition:
WARNING: vmlinux.o(.text+0x14c8): Section mismatch: reference to .init.data:vsyscall_int80_start (between 'fiddle_vdso' and 'xen_setup_features')

fiddle_vdso was only used from a __init function - so declare it __init.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:33:25 +01:00