Pass code model and stack alignment to the linker as these are not
stored in LLVM bitcode, and allow CONFIG_LTO_CLANG* to be enabled.
Signed-off-by: NSami Tolvanen <samitolvanen@google.com>
Reviewed-by: NKees Cook <keescook@chromium.org>

Clang incorrectly inlines functions with differing stack protector
attributes, which breaks __restore_processor_state() that relies on
stack protector being disabled. This change disables LTO for cpu.c
to work aroung the bug.

Link: https://bugs.llvm.org/show_bug.cgi?id=47479Suggested-by: NNick Desaulniers <ndesaulniers@google.com>
Signed-off-by: NSami Tolvanen <samitolvanen@google.com>

Disable LTO for the vDSO. Note that while we could use Clang's LTO
for the 64-bit vDSO, it won't add noticeable benefit for the small
amount of C code.
Signed-off-by: NSami Tolvanen <samitolvanen@google.com>
Reviewed-by: NKees Cook <keescook@chromium.org>

Select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION is selected to use
objtool to generate __mcount_loc sections for dynamic ftrace with
Clang and gcc <5 (later versions of gcc use -mrecord-mcount).
Signed-off-by: NSami Tolvanen <samitolvanen@google.com>
Reviewed-by: NKees Cook <keescook@chromium.org>

The 'syscall' variables are not directly used in the commands.
Remove the $(srctree)/ prefix because we can rely on VPATH.
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

The rules in these Makefiles cannot detect the command line change
because the prerequisite 'FORCE' is missing.

Adding 'FORCE' will result in the headers being rebuilt every time
because the 'targets' additions are also wrong; the file paths in
'targets' must be relative to the current Makefile.

Fix all of them so the if_changed rules work correctly.
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>

Allow building x86 with PREEMPT_DYNAMIC=n, this is needed for
PREEMPT_RT as it makes no sense to not have full preemption on
PREEMPT_RT.

Fixes: 8c98e8cf723c ("preempt/dynamic: Provide preempt_schedule[_notrace]() static calls")
Reported-by: NMike Galbraith <efault@gmx.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Tested-by: NMike Galbraith <efault@gmx.de>
Link: https://lkml.kernel.org/r/YCK1+JyFNxQnWeXK@hirez.programming.kicks-ass.net

Following the idle loop model, cleanly check for pending rcuog wakeup
before the last rescheduling point upon resuming to guest mode. This
way we can avoid to do it from rcu_user_enter() with the last resort
self-IPI hack that enforces rescheduling.
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20210131230548.32970-6-frederic@kernel.org

Use the new EXPORT_STATIC_CALL_TRAMP() / static_call_mod() to unexport
the static_call_key for the PREEMPT_DYNAMIC calls such that modules
can no longer update these calls.

Having modules change/hi-jack the preemption calls would be horrible.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

When exporting static_call_key; with EXPORT_STATIC_CALL*(), the module
can use static_call_update() to change the function called.  This is
not desirable in general.

Not exporting static_call_key however also disallows usage of
static_call(), since objtool needs the key to construct the
static_call_site.

Solve this by allowing objtool to create the static_call_site using
the trampoline address when it builds a module and cannot find the
static_call_key symbol. The module loader will then try and map the
trampole back to a key before it constructs the normal sites list.

Doing this requires a trampoline -> key associsation, so add another
magic section that keeps those.
Originally-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210127231837.ifddpn7rhwdaepiu@treble

Provide static calls to control preempt_schedule[_notrace]()
(called in CONFIG_PREEMPT) so that we can override their behaviour when
preempt= is overriden.

Since the default behaviour is full preemption, both their calls are
initialized to the arch provided wrapper, if any.

[fweisbec: only define static calls when PREEMPT_DYNAMIC, make it less
           dependent on x86 with __preempt_schedule_func]
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210118141223.123667-7-frederic@kernel.org

Preemption mode selection is currently hardcoded on Kconfig choices.
Introduce a dedicated option to tune preemption flavour at boot time,

This will be only available on architectures efficiently supporting
static calls in order not to tempt with the feature against additional
overhead that might be prohibitive or undesirable.

CONFIG_PREEMPT_DYNAMIC is automatically selected by CONFIG_PREEMPT if
the architecture provides the necessary support (CONFIG_STATIC_CALL_INLINE,
CONFIG_GENERIC_ENTRY, and provide with __preempt_schedule_function() /
__preempt_schedule_notrace_function()).
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NFrederic Weisbecker <frederic@kernel.org>
[peterz: relax requirement to HAVE_STATIC_CALL]
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210118141223.123667-5-frederic@kernel.org

Provide a stub function that return 0 and wire up the static call site
patching to replace the CALL with a single 5 byte instruction that
clears %RAX, the return value register.

The function can be cast to any function pointer type that has a
single %RAX return (including pointers). Also provide a version that
returns an int for convenience. We are clearing the entire %RAX register
in any case, whether the return value is 32 or 64 bits, since %RAX is
always a scratch register anyway.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210118141223.123667-2-frederic@kernel.org

Update Copyright year and drop file names from files themselves.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

After the commit f1be6cda ("x86/platform/intel-mid: Make
intel_scu_device_register() static") the platform_device.h is not being
used anymore by intel-mid.h. Remove it.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Since there is no more user of this global variable and associated custom API,
we may safely drop this legacy reinvented a wheel from the kernel sources.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The header is used by a single user. Move header content to that user.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Describe missed parameter in documentation of type1_access_ok().
Otherwise "make W=1 arch/x86/pci/" produces the following warning:
  CHECK   arch/x86/pci/intel_mid_pci.c
  CC      arch/x86/pci/intel_mid_pci.o
  arch/x86/pci/intel_mid_pci.c:152: warning: Function parameter or member 'reg' not described in 'type1_access_ok'
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Switch the platform code to use x86_id_table and accompanying API
instead of custom comparison against x86 CPU model.

This is one of the last users of custom API for that and following
changes will remove it for the good.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

SFI-based platforms are gone. So does this framework.

This removes mention of SFI through the drivers and other code as well.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NHans de Goede <hdegoede@redhat.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We should not set up further state if either mapping failed; paying
attention to just the user mapping's status isn't enough.

Also use GNTST_okay instead of implying its value (zero).

This is part of XSA-361.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Cc: stable@vger.kernel.org
Reviewed-by: NJuergen Gross <jgross@suse.com>
Signed-off-by: NJuergen Gross <jgross@suse.com>

Its sibling (set_foreign_p2m_mapping()) as well as the sibling of its
only caller (gnttab_map_refs()) don't clean up after themselves in case
of error. Higher level callers are expected to do so. However, in order
for that to really clean up any partially set up state, the operation
should not terminate upon encountering an entry in unexpected state. It
is particularly relevant to notice here that set_foreign_p2m_mapping()
would skip setting up a p2m entry if its grant mapping failed, but it
would continue to set up further p2m entries as long as their mappings
succeeded.

Arguably down the road set_foreign_p2m_mapping() may want its page state
related WARN_ON() also converted to an error return.

This is part of XSA-361.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Cc: stable@vger.kernel.org
Reviewed-by: NJuergen Gross <jgross@suse.com>
Signed-off-by: NJuergen Gross <jgross@suse.com>

This mostly reverts the old commit 3963333f ("uml: cover stubs
with a VMA") which had added a VMA to the existing PTEs. However,
there's no real reason to have the PTEs in the first place and the
VMA cannot be 'fixed' in place, which leads to bugs that userspace
could try to unmap them and be forcefully killed, or such. Also,
there's a bit of an ugly hole in userspace's address space.

Simplify all this: just install the stub code/page at the top of
the (inner) address space, i.e. put it just above TASK_SIZE. The
pages are simply hard-coded to be mapped in the userspace process
we use to implement an mm context, and they're out of reach of the
inner mmap/munmap/mprotect etc. since they're above TASK_SIZE.

Getting rid of the VMA also makes vma_merge() no longer hit one of
the VM_WARN_ON()s there because we installed a VMA while the code
assumes the stack VMA is the first one.

It also removes a lockdep warning about mmap_sem usage since we no
longer have uml_setup_stubs() and thus no longer need to do any
manipulation that would require mmap_sem in activate_mm().
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>

The userspace stacks mostly have a stack (and in the case of the
syscall stub we can just set their stack pointer) that points to
the location of the stub data page already.

Rework the stubs to use the stack pointer to derive the start of
the data page, rather than requiring it to be hard-coded.

In the clone stub, also integrate the int3 into the stack remap,
since we really must not use the stack while we remap it.

This prepares for putting the stub at a variable location that's
not part of the normal address space of the userspace processes
running inside the UML machine.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>

If the two are mixed up, then it looks as though the parent
returned an error if the child failed (before) the mmap(),
and then the resulting process never gets killed. Fix this
by splitting the child and parent errors, reporting and
using them appropriately.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>

Since both sleepable and non-sleepable programs execute under migrate_disable
add recursion prevention mechanism to both types of programs when they're
executed via bpf trampoline.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-5-alexei.starovoitov@gmail.com

Since sleepable programs don't migrate from the cpu the excution stats can be
computed for them as well. Reuse the same infrastructure for both sleepable and
non-sleepable programs.

run_cnt     -> the number of times the program was executed.
run_time_ns -> the program execution time in nanoseconds including the
               off-cpu time when the program was sleeping.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAndrii Nakryiko <andrii@kernel.org>
Acked-by: NKP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-4-alexei.starovoitov@gmail.com

Add a 2 byte pad to struct compat_vcpu_info so that the sum size of its
fields is actually 64 bytes.  The effective size without the padding is
also 64 bytes due to the compiler aligning evtchn_pending_sel to a 4-byte
boundary, but depending on compiler alignment is subtle and unnecessary.

Opportunistically replace spaces with tables in the other fields.

Cc: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: NSean Christopherson <seanjc@google.com>
Message-Id: <20210210182609.435200-6-seanjc@google.com>
Reviewed-by: NDavid Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The sparse tool complains as follows:

arch/x86/kvm/svm/svm.c:204:6: warning:
 symbol 'svm_gp_erratum_intercept' was not declared. Should it be static?

This symbol is not used outside of svm.c, so this
commit marks it static.

Fixes: 82a11e9c ("KVM: SVM: Add emulation support for #GP triggered by SVM instructions")
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Message-Id: <20210210075958.1096317-1-weiyongjun1@huawei.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Just like MSI/MSI-X, IO-APIC interrupts are remapped by Microsoft
Hypervisor when Linux runs as the root partition. Implement an IRQ
domain to handle mapping and unmapping of IO-APIC interrupts.
Signed-off-by: NWei Liu <wei.liu@kernel.org>
Acked-by: NJoerg Roedel <joro@8bytes.org>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-17-wei.liu@kernel.org

When Linux runs as the root partition on Microsoft Hypervisor, its
interrupts are remapped.  Linux will need to explicitly map and unmap
interrupts for hardware.

Implement an MSI domain to issue the correct hypercalls. And initialize
this irq domain as the default MSI irq domain.
Signed-off-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Co-Developed-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: NWei Liu <wei.liu@kernel.org>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-16-wei.liu@kernel.org

Signed-off-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Co-Developed-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: NWei Liu <wei.liu@kernel.org>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-15-wei.liu@kernel.org

We will soon need to access fields inside the MSI address and MSI data
fields. Introduce hv_msi_address_register and hv_msi_data_register.

Fix up one user of hv_msi_entry in mshyperv.h.

No functional change expected.
Signed-off-by: NWei Liu <wei.liu@kernel.org>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-12-wei.liu@kernel.org

Microsoft Hypervisor requires the root partition to make a few
hypercalls to setup application processors before they can be used.
Signed-off-by: NLillian Grassin-Drake <ligrassi@microsoft.com>
Signed-off-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Co-Developed-by: NLillian Grassin-Drake <ligrassi@microsoft.com>
Co-Developed-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: NWei Liu <wei.liu@kernel.org>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-11-wei.liu@kernel.org

They are used to deposit pages into Microsoft Hypervisor and bring up
logical and virtual processors.
Signed-off-by: NLillian Grassin-Drake <ligrassi@microsoft.com>
Signed-off-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: NNuno Das Neves <nunodasneves@linux.microsoft.com>
Co-Developed-by: NLillian Grassin-Drake <ligrassi@microsoft.com>
Co-Developed-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Co-Developed-by: NNuno Das Neves <nunodasneves@linux.microsoft.com>
Signed-off-by: NWei Liu <wei.liu@kernel.org>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-10-wei.liu@kernel.org

When Linux is running as the root partition, the hypercall page will
have already been setup by Hyper-V. Copy the content over to the
allocated page.

Add checks to hv_suspend & co to bail early because they are not
supported in this setup yet.
Signed-off-by: NLillian Grassin-Drake <ligrassi@microsoft.com>
Signed-off-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: NNuno Das Neves <nunodasneves@linux.microsoft.com>
Co-Developed-by: NLillian Grassin-Drake <ligrassi@microsoft.com>
Co-Developed-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Co-Developed-by: NNuno Das Neves <nunodasneves@linux.microsoft.com>
Signed-off-by: NWei Liu <wei.liu@kernel.org>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-8-wei.liu@kernel.org

We will need the partition ID for executing some hypercalls later.
Signed-off-by: NLillian Grassin-Drake <ligrassi@microsoft.com>
Co-Developed-by: NSunil Muthuswamy <sunilmut@microsoft.com>
Signed-off-by: NWei Liu <wei.liu@kernel.org>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-7-wei.liu@kernel.org

When Linux runs as the root partition, it will need to make hypercalls
which return data from the hypervisor.

Allocate pages for storing results when Linux runs as the root
partition.
Signed-off-by: NLillian Grassin-Drake <ligrassi@microsoft.com>
Co-Developed-by: NLillian Grassin-Drake <ligrassi@microsoft.com>
Signed-off-by: NWei Liu <wei.liu@kernel.org>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-6-wei.liu@kernel.org

For now we can use the privilege flag to check. Stash the value to be
used later.

Put in a bunch of defines for future use when we want to have more
fine-grained detection.
Signed-off-by: NWei Liu <wei.liu@kernel.org>
Reviewed-by: NPavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: NMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20210203150435.27941-3-wei.liu@kernel.org

If bit 22 of Group B Features is set, the guest has access to the
Isolation Configuration CPUID leaf.  On x86, the first four bits
of EAX in this leaf provide the isolation type of the partition;
we entail three isolation types: 'SNP' (hardware-based isolation),
'VBS' (software-based isolation), and 'NONE' (no isolation).
Signed-off-by: NAndrea Parri (Microsoft) <parri.andrea@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: x86@kernel.org
Cc: linux-arch@vger.kernel.org
Link: https://lore.kernel.org/r/20210201144814.2701-2-parri.andrea@gmail.comReviewed-by: NMichael Kelley <mikelley@microsoft.com>
Signed-off-by: NWei Liu <wei.liu@kernel.org>