Commit Graph

184 Commits

Author SHA1 Message Date
Juergen Gross 11af36cb89 x86/paravirt: Convert simple paravirt functions to asm
All functions referenced via __PV_IS_CALLEE_SAVE() need to be assembler
functions, as those functions calls are hidden from the compiler.

In case the kernel is compiled with "-fzero-call-used-regs" the compiler
will clobber caller-saved registers at the end of C functions, which
will result in unexpectedly zeroed registers at the call site of the
related paravirt functions.

Replace the C functions with DEFINE_PARAVIRT_ASM() constructs using
the same instructions as the related paravirt calls in the
PVOP_ALT_[V]CALLEE*() macros. And since they're not C functions visible
to the compiler anymore, latter won't do the callee-clobbered zeroing
invoked by -fzero-call-used-regs and thus won't corrupt registers.

  [ bp: Extend commit message. ]

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230317063325.361-1-jgross@suse.com
2023-03-17 13:29:47 +01:00
Juergen Gross c9ae1b10d9 x86/paravirt: Merge activate_mm() and dup_mmap() callbacks
The two paravirt callbacks .mmu.activate_mm() and .mmu.dup_mmap() are
sharing the same implementations in all cases: for Xen PV guests they
are pinning the PGD of the new mm_struct, and for all other cases they
are a NOP.

In the end, both callbacks are meant to register an address space with
the underlying hypervisor, so there needs to be only a single callback
for that purpose.

So merge them to a common callback .mmu.enter_mmap() (in contrast to the
corresponding already existing .mmu.exit_mmap()).

As the first parameter of the old callbacks isn't used, drop it from the
replacement one.

  [ bp: Remove last occurrence of paravirt_activate_mm() in
    asm/mmu_context.h ]

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Link: https://lore.kernel.org/r/20230207075902.7539-1-jgross@suse.com
2023-03-06 09:41:37 +01:00
Linus Torvalds 877934769e - Cache the AMD debug registers in per-CPU variables to avoid MSR writes
where possible, when supporting a debug registers swap feature for
   SEV-ES guests
 
 - Add support for AMD's version of eIBRS called Automatic IBRS which is
   a set-and-forget control of indirect branch restriction speculation
   resources on privilege change
 
 - Add support for a new x86 instruction - LKGS - Load kernel GS which is
   part of the FRED infrastructure
 
 - Reset SPEC_CTRL upon init to accomodate use cases like kexec which
   rediscover
 
 - Other smaller fixes and cleanups
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Merge tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cpuid updates from Borislav Petkov:

 - Cache the AMD debug registers in per-CPU variables to avoid MSR
   writes where possible, when supporting a debug registers swap feature
   for SEV-ES guests

 - Add support for AMD's version of eIBRS called Automatic IBRS which is
   a set-and-forget control of indirect branch restriction speculation
   resources on privilege change

 - Add support for a new x86 instruction - LKGS - Load kernel GS which
   is part of the FRED infrastructure

 - Reset SPEC_CTRL upon init to accomodate use cases like kexec which
   rediscover

 - Other smaller fixes and cleanups

* tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/amd: Cache debug register values in percpu variables
  KVM: x86: Propagate the AMD Automatic IBRS feature to the guest
  x86/cpu: Support AMD Automatic IBRS
  x86/cpu, kvm: Add the SMM_CTL MSR not present feature
  x86/cpu, kvm: Add the Null Selector Clears Base feature
  x86/cpu, kvm: Move X86_FEATURE_LFENCE_RDTSC to its native leaf
  x86/cpu, kvm: Add the NO_NESTED_DATA_BP feature
  KVM: x86: Move open-coded CPUID leaf 0x80000021 EAX bit propagation code
  x86/cpu, kvm: Add support for CPUID_80000021_EAX
  x86/gsseg: Add the new <asm/gsseg.h> header to <asm/asm-prototypes.h>
  x86/gsseg: Use the LKGS instruction if available for load_gs_index()
  x86/gsseg: Move load_gs_index() to its own new header file
  x86/gsseg: Make asm_load_gs_index() take an u16
  x86/opcode: Add the LKGS instruction to x86-opcode-map
  x86/cpufeature: Add the CPU feature bit for LKGS
  x86/bugs: Reset speculation control settings on init
  x86/cpu: Remove redundant extern x86_read_arch_cap_msr()
2023-02-21 14:51:40 -08:00
Peter Zijlstra 10a099405f cpuidle, xenpv: Make more PARAVIRT_XXL noinstr clean
objtool found a few cases where this code called out into instrumented
code:

  vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section
  vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section
  vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section

Solve this by:

 - marking arch_safe_halt(), wbinvd(), native_wbinvd() and
   HYPERVISOR_sched_op() as __always_inline().

 - Explicitly uninlining xen_safe_halt() and pv_native_wbinvd() [they were
   already uninlined by the compiler on use as function pointers] and
   annotating them as 'noinstr'.

 - Annotating pv_native_safe_halt() as 'noinstr'.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195541.171918174@infradead.org
2023-01-13 11:48:16 +01:00
H. Peter Anvin (Intel) ae53fa1870 x86/gsseg: Move load_gs_index() to its own new header file
GS is a special segment on x86_64, move load_gs_index() to its own new
header file to simplify header inclusion.

No change in functionality.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230112072032.35626-5-xin3.li@intel.com
2023-01-12 13:06:36 +01:00
Juergen Gross f1a033cc6b x86/paravirt: Use common macro for creating simple asm paravirt functions
There are some paravirt assembler functions which are sharing a common
pattern. Introduce a macro DEFINE_PARAVIRT_ASM() for creating them.

Note that this macro is including explicit alignment of the generated
functions, leading to __raw_callee_save___kvm_vcpu_is_preempted(),
_paravirt_nop() and paravirt_ret0() to be aligned at 4 byte boundaries
now.

The explicit _paravirt_nop() prototype in paravirt.c isn't needed, as
it is included in paravirt_types.h already.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Link: https://lkml.kernel.org/r/20221109134418.6516-1-jgross@suse.com
2022-11-24 13:56:44 +01:00
Thomas Gleixner 1d293758e5 x86/paravirt: Properly align PV functions
Ensure inline asm functions are consistently aligned with compiler
generated and SYM_FUNC_START*() functions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220915111144.038540008@infradead.org
2022-10-17 16:40:59 +02:00
Peter Zijlstra c3b037917c x86/ibt,paravirt: Sprinkle ENDBR
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154318.051635891@infradead.org
2022-03-15 10:32:36 +01:00
Peter Zijlstra 8b87d8cec1 x86/entry,xen: Early rewrite of restore_regs_and_return_to_kernel()
By doing an early rewrite of 'jmp native_iret` in
restore_regs_and_return_to_kernel() we can get rid of the last
INTERRUPT_RETURN user and paravirt_iret.

Suggested-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.815039833@infradead.org
2022-03-15 10:32:34 +01:00
Peter Zijlstra ba27d1a808 x86/ibt,paravirt: Use text_gen_insn() for paravirt_patch()
Less duplication is more better.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.697253958@infradead.org
2022-03-15 10:32:34 +01:00
Peter Zijlstra b17c2baa30 x86: Prepare inline-asm for straight-line-speculation
Replace all ret/retq instructions with ASM_RET in preparation of
making it more than a single instruction.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211204134907.964635458@infradead.org
2021-12-08 19:23:12 +01:00
Paolo Bonzini b9ecb9a997 Merge branch 'kvm-guest-sev-migration' into kvm-master
Add guest api and guest kernel support for SEV live migration.

Introduces a new hypercall to notify the host of changes to the page
encryption status.  If the page is encrypted then it must be migrated
through the SEV firmware or a helper VM sharing the key.  If page is
not encrypted then it can be migrated normally by userspace.  This new
hypercall is invoked using paravirt_ops.

Conflicts: sev_active() replaced by cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT).
2021-11-11 07:40:26 -05:00
Brijesh Singh 064ce6c550 mm: x86: Invoke hypercall when page encryption status is changed
Invoke a hypercall when a memory region is changed from encrypted ->
decrypted and vice versa. Hypervisor needs to know the page encryption
status during the guest migration.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Steve Rutherford <srutherford@google.com>
Reviewed-by: Venu Busireddy <venu.busireddy@oracle.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Message-Id: <0a237d5bb08793916c7790a3e653a2cbe7485761.1629726117.git.ashish.kalra@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-11 07:37:24 -05:00
Juergen Gross e453f872b7 x86/xen: switch initial pvops IRQ functions to dummy ones
The initial pvops functions handling irq flags will only ever be called
before interrupts are being enabled.

So switch them to be dummy functions:
- xen_save_fl() can always return 0
- xen_irq_disable() is a nop
- xen_irq_enable() can BUG()

Add some generic paravirt functions for that purpose.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20211028072748.29862-3-jgross@suse.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-02 08:03:43 -05:00
Peter Zijlstra 09c413071e x86/xen: Make irq_disable() noinstr
vmlinux.o: warning: objtool: pv_ops[31]: native_irq_disable
vmlinux.o: warning: objtool: pv_ops[31]: __raw_callee_save_xen_irq_disable
vmlinux.o: warning: objtool: pv_ops[31]: xen_irq_disable_direct
vmlinux.o: warning: objtool: lock_is_held_type()+0x5b: call to pv_ops[31]() 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/20210624095148.933869441@infradead.org
2021-09-17 13:20:23 +02:00
Peter Zijlstra d7bfc7d57c x86/xen: Make irq_enable() noinstr
vmlinux.o: warning: objtool: pv_ops[32]: native_irq_enable
vmlinux.o: warning: objtool: pv_ops[32]: __raw_callee_save_xen_irq_enable
vmlinux.o: warning: objtool: pv_ops[32]: xen_irq_enable_direct
vmlinux.o: warning: objtool: lock_is_held_type()+0xfe: call to pv_ops[32]() 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/20210624095148.872254932@infradead.org
2021-09-17 13:17:12 +02:00
Peter Zijlstra 7361fac046 x86/xen: Make set_debugreg() noinstr
vmlinux.o: warning: objtool: pv_ops[2]: xen_set_debugreg
vmlinux.o: warning: objtool: pv_ops[2]: native_set_debugreg
vmlinux.o: warning: objtool: exc_debug()+0x3b: call to pv_ops[2]() 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/20210624095148.687755639@infradead.org
2021-09-17 13:14:39 +02:00
Peter Zijlstra f4afb713e5 x86/xen: Make get_debugreg() noinstr
vmlinux.o: warning: objtool: pv_ops[1]: xen_get_debugreg
vmlinux.o: warning: objtool: pv_ops[1]: native_get_debugreg
vmlinux.o: warning: objtool: exc_debug()+0x25: call to pv_ops[1]() 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/20210624095148.625523645@infradead.org
2021-09-17 13:12:34 +02:00
Peter Zijlstra 209cfd0cbb x86/xen: Make write_cr2() noinstr
vmlinux.o: warning: objtool: pv_ops[42]: native_write_cr2
vmlinux.o: warning: objtool: pv_ops[42]: xen_write_cr2
vmlinux.o: warning: objtool: exc_nmi()+0x127: call to pv_ops[42]() 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/20210624095148.563524913@infradead.org
2021-09-17 13:12:16 +02:00
Peter Zijlstra 0a53c9acf4 x86/xen: Make read_cr2() noinstr
vmlinux.o: warning: objtool: pv_ops[41]: native_read_cr2
vmlinux.o: warning: objtool: pv_ops[41]: xen_read_cr2
vmlinux.o: warning: objtool: pv_ops[41]: xen_read_cr2_direct
vmlinux.o: warning: objtool: exc_double_fault()+0x15: call to pv_ops[41]() 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/20210624095148.500331616@infradead.org
2021-09-17 13:11:50 +02:00
Linus Torvalds 635de956a7 The x86 MM changes in this cycle were:
- Implement concurrent TLB flushes, which overlaps the local TLB flush with the
    remote TLB flush. In testing this improved sysbench performance measurably by
    a couple of percentage points, especially if TLB-heavy security mitigations
    are active.
 
  - Further micro-optimizations to improve the performance of TLB flushes.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'x86-mm-2021-04-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 tlb updates from Ingo Molnar:
 "The x86 MM changes in this cycle were:

   - Implement concurrent TLB flushes, which overlaps the local TLB
     flush with the remote TLB flush.

     In testing this improved sysbench performance measurably by a
     couple of percentage points, especially if TLB-heavy security
     mitigations are active.

   - Further micro-optimizations to improve the performance of TLB
     flushes"

* tag 'x86-mm-2021-04-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp: Micro-optimize smp_call_function_many_cond()
  smp: Inline on_each_cpu_cond() and on_each_cpu()
  x86/mm/tlb: Remove unnecessary uses of the inline keyword
  cpumask: Mark functions as pure
  x86/mm/tlb: Do not make is_lazy dirty for no reason
  x86/mm/tlb: Privatize cpu_tlbstate
  x86/mm/tlb: Flush remote and local TLBs concurrently
  x86/mm/tlb: Open-code on_each_cpu_cond_mask() for tlb_is_not_lazy()
  x86/mm/tlb: Unify flush_tlb_func_local() and flush_tlb_func_remote()
  smp: Run functions concurrently in smp_call_function_many_cond()
2021-04-29 11:41:43 -07:00
Juergen Gross 054ac8ad5e x86/paravirt: Have only one paravirt patch function
There is no need any longer to have different paravirt patch functions
for native and Xen. Eliminate native_patch() and rename
paravirt_patch_default() to paravirt_patch().

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-15-jgross@suse.com
2021-03-11 20:11:09 +01:00
Juergen Gross fafe5e7422 x86/paravirt: Switch functions with custom code to ALTERNATIVE
Instead of using paravirt patching for custom code sequences use
ALTERNATIVE for the functions with custom code replacements.

Instead of patching an ud2 instruction for unpopulated vector entries
into the caller site, use a simple function just calling BUG() as a
replacement.

Simplify the register defines for assembler paravirt calling, as there
isn't much usage left.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-14-jgross@suse.com
2021-03-11 20:07:01 +01:00
Juergen Gross ae755b5a45 x86/paravirt: Switch iret pvops to ALTERNATIVE
The iret paravirt op is rather special as it is using a jmp instead
of a call instruction. Switch it to ALTERNATIVE.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-12-jgross@suse.com
2021-03-11 19:58:54 +01:00
Juergen Gross a0e2bf7cb7 x86/paravirt: Switch time pvops functions to use static_call()
The time pvops functions are the only ones left which might be
used in 32-bit mode and which return a 64-bit value.

Switch them to use the static_call() mechanism instead of pvops, as
this allows quite some simplification of the pvops implementation.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-5-jgross@suse.com
2021-03-11 16:17:52 +01:00
Nadav Amit 4ce94eabac x86/mm/tlb: Flush remote and local TLBs concurrently
To improve TLB shootdown performance, flush the remote and local TLBs
concurrently. Introduce flush_tlb_multi() that does so. Introduce
paravirtual versions of flush_tlb_multi() for KVM, Xen and hyper-v (Xen
and hyper-v are only compile-tested).

While the updated smp infrastructure is capable of running a function on
a single local core, it is not optimized for this case. The multiple
function calls and the indirect branch introduce some overhead, and
might make local TLB flushes slower than they were before the recent
changes.

Before calling the SMP infrastructure, check if only a local TLB flush
is needed to restore the lost performance in this common case. This
requires to check mm_cpumask() one more time, but unless this mask is
updated very frequently, this should impact performance negatively.

Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com> # Hyper-v parts
Reviewed-by: Juergen Gross <jgross@suse.com> # Xen and paravirt parts
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20210220231712.2475218-5-namit@vmware.com
2021-03-06 12:59:10 +01:00
Juergen Gross ab234a260b x86/pv: Rework arch_local_irq_restore() to not use popf
POPF is a rather expensive operation, so don't use it for restoring
irq flags. Instead, test whether interrupts are enabled in the flags
parameter and enable interrupts via STI in that case.

This results in the restore_fl paravirt op to be no longer needed.

Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210120135555.32594-7-jgross@suse.com
2021-02-10 12:36:45 +01:00
Juergen Gross afd30525a6 x86/xen: Drop USERGS_SYSRET64 paravirt call
USERGS_SYSRET64 is used to return from a syscall via SYSRET, but
a Xen PV guest will nevertheless use the IRET hypercall, as there
is no sysret PV hypercall defined.

So instead of testing all the prerequisites for doing a sysret and
then mangling the stack for Xen PV again for doing an iret just use
the iret exit from the beginning.

This can easily be done via an ALTERNATIVE like it is done for the
sysenter compat case already.

It should be noted that this drops the optimization in Xen for not
restoring a few registers when returning to user mode, but it seems
as if the saved instructions in the kernel more than compensate for
this drop (a kernel build in a Xen PV guest was slightly faster with
this patch applied).

While at it remove the stale sysret32 remnants.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210120135555.32594-6-jgross@suse.com
2021-02-10 12:32:07 +01:00
Juergen Gross 53c9d92409 x86/pv: Switch SWAPGS to ALTERNATIVE
SWAPGS is used only for interrupts coming from user mode or for
returning to user mode. So there is no reason to use the PARAVIRT
framework, as it can easily be replaced by an ALTERNATIVE depending
on X86_FEATURE_XENPV.

There are several instances using the PV-aware SWAPGS macro in paths
which are never executed in a Xen PV guest. Replace those with the
plain swapgs instruction. For SWAPGS_UNSAFE_STACK the same applies.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210120135555.32594-5-jgross@suse.com
2021-02-10 12:25:49 +01:00
Juergen Gross e1ac3e66d3 x86/paravirt: Remove set_pte_at() pv-op
On x86 set_pte_at() is now always falling back to set_pte(). So instead
of having this fallback after the paravirt maze just drop the
set_pte_at paravirt operation and let set_pte_at() use the set_pte()
function directly.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200815100641.26362-6-jgross@suse.com
2020-08-15 13:52:12 +02:00
Juergen Gross 0cabf99149 x86/paravirt: Remove 32-bit support from CONFIG_PARAVIRT_XXL
The last 32-bit user of stuff under CONFIG_PARAVIRT_XXL is gone.

Remove 32-bit specific parts.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200815100641.26362-2-jgross@suse.com
2020-08-15 13:52:11 +02:00
Andy Lutomirski cadfad8701 x86/ioperm: Fix io bitmap invalidation on Xen PV
tss_invalidate_io_bitmap() wasn't wired up properly through the pvop
machinery, so the TSS and Xen's io bitmap would get out of sync
whenever disabling a valid io bitmap.

Add a new pvop for tss_invalidate_io_bitmap() to fix it.

This is XSA-329.

Fixes: 22fe5b0439 ("x86/ioperm: Move TSS bitmap update to exit to user work")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/d53075590e1f91c19f8af705059d3ff99424c020.1595030016.git.luto@kernel.org
2020-07-18 12:31:49 +02:00
Mike Rapoport 65fddcfca8 mm: reorder includes after introduction of linux/pgtable.h
The replacement of <asm/pgrable.h> with <linux/pgtable.h> made the include
of the latter in the middle of asm includes.  Fix this up with the aid of
the below script and manual adjustments here and there.

	import sys
	import re

	if len(sys.argv) is not 3:
	    print "USAGE: %s <file> <header>" % (sys.argv[0])
	    sys.exit(1)

	hdr_to_move="#include <linux/%s>" % sys.argv[2]
	moved = False
	in_hdrs = False

	with open(sys.argv[1], "r") as f:
	    lines = f.readlines()
	    for _line in lines:
		line = _line.rstrip('
')
		if line == hdr_to_move:
		    continue
		if line.startswith("#include <linux/"):
		    in_hdrs = True
		elif not moved and in_hdrs:
		    moved = True
		    print hdr_to_move
		print line

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport ca5999fde0 mm: introduce include/linux/pgtable.h
The include/linux/pgtable.h is going to be the home of generic page table
manipulation functions.

Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and
make the latter include asm/pgtable.h.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Thomas Gleixner 127ac915c8 x86/tlb: Move __flush_tlb_one_user() out of line
cpu_tlbstate is exported because various TLB-related functions need access
to it, but cpu_tlbstate is sensitive information which should only be
accessed by well-contained kernel functions and not be directly exposed to
modules.

As a third step, move _flush_tlb_one_user() out of line and hide the
native function. The latter can be static when CONFIG_PARAVIRT is
disabled.

Consolidate the name space while at it and remove the pointless extra
wrapper in the paravirt code.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200421092559.428213098@linutronix.de
2020-04-26 11:00:29 +02:00
Thomas Gleixner cd30d26cf3 x86/tlb: Move __flush_tlb_global() out of line
cpu_tlbstate is exported because various TLB-related functions need
access to it, but cpu_tlbstate is sensitive information which should
only be accessed by well-contained kernel functions and not be directly
exposed to modules.

As a second step, move __flush_tlb_global() out of line and hide the
native function. The latter can be static when CONFIG_PARAVIRT is
disabled.

Consolidate the namespace while at it and remove the pointless extra
wrapper in the paravirt code.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200421092559.336916818@linutronix.de
2020-04-26 11:00:27 +02:00
Thomas Gleixner 2faf153bb7 x86/tlb: Move __flush_tlb() out of line
cpu_tlbstate is exported because various TLB-related functions need
access to it, but cpu_tlbstate is sensitive information which should
only be accessed by well-contained kernel functions and not be directly
exposed to modules.

As a first step, move __flush_tlb() out of line and hide the native
function. The latter can be static when CONFIG_PARAVIRT is disabled.

Consolidate the namespace while at it and remove the pointless extra
wrapper in the paravirt code.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200421092559.246130908@linutronix.de
2020-04-26 11:00:05 +02:00
Juergen Gross 99bcd4a6e5 x86/ioperm: Add new paravirt function update_io_bitmap()
Commit 111e7b15cf ("x86/ioperm: Extend IOPL config to control ioperm()
as well") reworked the iopl syscall to use I/O bitmaps.

Unfortunately this broke Xen PV domains using that syscall as there is
currently no I/O bitmap support in PV domains.

Add I/O bitmap support via a new paravirt function update_io_bitmap which
Xen PV domains can use to update their I/O bitmaps via a hypercall.

Fixes: 111e7b15cf ("x86/ioperm: Extend IOPL config to control ioperm() as well")
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Cc: <stable@vger.kernel.org> # 5.5
Link: https://lkml.kernel.org/r/20200218154712.25490-1-jgross@suse.com
2020-02-29 12:43:09 +01:00
Thomas Gleixner a24ca99768 x86/iopl: Remove legacy IOPL option
The IOPL emulation via the I/O bitmap is sufficient. Remove the legacy
cruft dealing with the (e)flags based IOPL mechanism.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com> (Paravirt and Xen parts)
Acked-by: Andy Lutomirski <luto@kernel.org>
2019-11-16 11:24:05 +01:00
Andrew Cooper 83b584d9c6 x86/paravirt: Drop {read,write}_cr8() hooks
There is a lot of infrastructure for functionality which is used
exclusively in __{save,restore}_processor_state() on the suspend/resume
path.

cr8 is an alias of APIC_TASKPRI, and APIC_TASKPRI is saved/restored by
lapic_{suspend,resume}().  Saving and restoring cr8 independently of the
rest of the Local APIC state isn't a clever thing to be doing.

Delete the suspend/resume cr8 handling, which shrinks the size of struct
saved_context, and allows for the removal of both PVOPS.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20190715151641.29210-1-andrew.cooper3@citrix.com
2019-07-22 10:12:33 +02:00
Peter Zijlstra 55aedddb61 x86/paravirt: Make read_cr2() CALLEE_SAVE
The one paravirt read_cr2() implementation (Xen) is actually quite trivial
and doesn't need to clobber anything other than the return register.

Making read_cr2() CALLEE_SAVE avoids all the PUSH/POP nonsense and allows
more convenient use from assembly.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: bp@alien8.de
Cc: rostedt@goodmis.org
Cc: luto@kernel.org
Cc: torvalds@linux-foundation.org
Cc: hpa@zytor.com
Cc: dave.hansen@linux.intel.com
Cc: zhe.he@windriver.com
Cc: joel@joelfernandes.org
Cc: devel@etsukata.com
Link: https://lkml.kernel.org/r/20190711114335.887392493@infradead.org
2019-07-17 23:17:37 +02:00
Linus Torvalds da17702385 Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 paravirt updates from Ingo Molnar:
 "A handful of paravirt patching code enhancements to make it more
  robust against patching failures, and related cleanups and not so
  related cleanups - by Thomas Gleixner and myself"

* 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/paravirt: Rename paravirt_patch_site::instrtype to paravirt_patch_site::type
  x86/paravirt: Standardize 'insn_buff' variable names
  x86/paravirt: Match paravirt patchlet field definition ordering to initialization ordering
  x86/paravirt: Replace the paravirt patch asm magic
  x86/paravirt: Unify the 32/64 bit paravirt patching code
  x86/paravirt: Detect over-sized patching bugs in paravirt_patch_call()
  x86/paravirt: Detect over-sized patching bugs in paravirt_patch_insns()
  x86/paravirt: Remove bogus extern declarations
2019-07-08 17:34:44 -07:00
Thomas Gleixner fd534e9b5f treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 102
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  51 franklin st fifth floor boston ma 02110 1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 50 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091649.499889647@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:39:00 +02:00
Ingo Molnar 1fc654cf6e x86/paravirt: Standardize 'insn_buff' variable names
We currently have 6 (!) separate naming variants to name temporary instruction
buffers that are used for code patching:

 - insnbuf
 - insnbuff
 - insn_buff
 - insn_buffer
 - ibuf
 - ibuffer

These are used as local variables, percpu fields and function parameters.

Standardize all the names to a single variant: 'insn_buff'.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-29 16:05:49 +02:00
Ingo Molnar 11e86dc7f2 x86/paravirt: Detect over-sized patching bugs in paravirt_patch_call()
paravirt_patch_call() currently handles patching failures inconsistently:
we generate a warning in the retpoline case, but don't in other cases where
we might end up with a non-working kernel as well.

So just convert it all to a BUG_ON(), these patching calls are *not* supposed
to fail, and if they do we want to know it immediately.

This also makes the kernel smaller and removes an #ifdef ugly.

I tried it with a richly paravirt-enabled kernel and no patching bugs
were detected.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
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/20190425095039.GC115378@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-25 12:00:44 +02:00
Ingo Molnar 2777cae2b1 x86/paravirt: Detect over-sized patching bugs in paravirt_patch_insns()
So paravirt_patch_insns() contains this gem of logic:

unsigned paravirt_patch_insns(void *insnbuf, unsigned len,
                              const char *start, const char *end)
{
        unsigned insn_len = end - start;

        if (insn_len > len || start == NULL)
                insn_len = len;
        else
                memcpy(insnbuf, start, insn_len);

        return insn_len;
}

Note how 'len' (size of the original instruction) is checked against the new
instruction, and silently discarded with no warning printed whatsoever.

This crashes the kernel in funny ways if the patching template is buggy,
and usually in much later places.

Instead do a direct BUG_ON(), there's no way to continue successfully at that point.

I've tested this patch, with the vanilla kernel check never triggers, and
if I intentionally increase the size of one of the patch templates to a
too high value the assert triggers:

[    0.164385] kernel BUG at arch/x86/kernel/paravirt.c:167!

Without this patch a broken kernel randomly crashes in later places,
after the silent patching failure.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20190425091717.GA72229@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-25 12:00:31 +02:00
Borislav Petkov 67e87d43b7 x86: Convert some slow-path static_cpu_has() callers to boot_cpu_has()
Using static_cpu_has() is pointless on those paths, convert them to the
boot_cpu_has() variant.

No functional changes.

Reported-by: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Juergen Gross <jgross@suse.com> # for paravirt
Cc: Aubrey Li <aubrey.li@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
Cc: linux-edac@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: virtualization@lists.linux-foundation.org
Cc: x86@kernel.org
Link: https://lkml.kernel.org/r/20190330112022.28888-3-bp@alien8.de
2019-04-08 12:13:34 +02:00
Juergen Gross 7847c7be04 x86/paravirt: Remove unused _paravirt_ident_32
There is no user of _paravirt_ident_32 left in the tree. Remove it
together with the related paravirt_patch_ident_32().

paravirt_patch_ident_64() can be moved inside CONFIG_PARAVIRT_XXL=y.

Signed-off-by: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akataria@vmware.com
Cc: boris.ostrovsky@oracle.com
Cc: rusty@rustcorp.com.au
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20181030063301.15054-1-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-30 09:55:31 +01:00
Juergen Gross 8af1909580 x86/paravirt: Remove GPL from pv_ops export
Commit 5c83511bdb ("x86/paravirt: Use a single ops structure")
introduced a regression for out-of-tree modules using spinlocks, as
pv_lock_ops was exported via EXPORT_SYMBOL(), while the new pv_ops
structure now containing the pv lock operations is exported via
EXPORT_SYMBOL_GPL().

Change that by using EXPORT_SYMBOL(pv_ops).

Fixes: 5c83511bdb ("x86/paravirt: Use a single ops structure")
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel@lists.xenproject.org
Cc: virtualization@lists.linux-foundation.org
Cc: akataria@vmware.com
Cc: rusty@rustcorp.com.au
Cc: boris.ostrovsky@oracle.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20181029150116.25372-1-jgross@suse.com
2018-10-29 19:04:05 +01:00
Linus Torvalds f682a7920b Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 paravirt updates from Ingo Molnar:
 "Two main changes:

   - Remove no longer used parts of the paravirt infrastructure and put
     large quantities of paravirt ops under a new config option
     PARAVIRT_XXL=y, which is selected by XEN_PV only. (Joergen Gross)

   - Enable PV spinlocks on Hyperv (Yi Sun)"

* 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/hyperv: Enable PV qspinlock for Hyper-V
  x86/hyperv: Add GUEST_IDLE_MSR support
  x86/paravirt: Clean up native_patch()
  x86/paravirt: Prevent redefinition of SAVE_FLAGS macro
  x86/xen: Make xen_reservation_lock static
  x86/paravirt: Remove unneeded mmu related paravirt ops bits
  x86/paravirt: Move the Xen-only pv_mmu_ops under the PARAVIRT_XXL umbrella
  x86/paravirt: Move the pv_irq_ops under the PARAVIRT_XXL umbrella
  x86/paravirt: Move the Xen-only pv_cpu_ops under the PARAVIRT_XXL umbrella
  x86/paravirt: Move items in pv_info under PARAVIRT_XXL umbrella
  x86/paravirt: Introduce new config option PARAVIRT_XXL
  x86/paravirt: Remove unused paravirt bits
  x86/paravirt: Use a single ops structure
  x86/paravirt: Remove clobbers from struct paravirt_patch_site
  x86/paravirt: Remove clobbers parameter from paravirt patch functions
  x86/paravirt: Make paravirt_patch_call() and paravirt_patch_jmp() static
  x86/xen: Add SPDX identifier in arch/x86/xen files
  x86/xen: Link platform-pci-unplug.o only if CONFIG_XEN_PVHVM
  x86/xen: Move pv specific parts of arch/x86/xen/mmu.c to mmu_pv.c
  x86/xen: Move pv irq related functions under CONFIG_XEN_PV umbrella
2018-10-23 17:54:58 +01:00