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Manually generate the PDPTR reserved bit mask when explicitly loading
PDPTRs. The reserved bits that are being tracked by the MMU reflect the
current paging mode, which is unlikely to be PAE paging in the vast
majority of flows that use load_pdptrs(), e.g. CR0 and CR4 emulation,
__set_sregs(), etc... This can cause KVM to incorrectly signal a bad
PDPTR, or more likely, miss a reserved bit check and subsequently fail
a VM-Enter due to a bad VMCS.GUEST_PDPTR.
Add a one off helper to generate the reserved bits instead of sharing
code across the MMU's calculations and the PDPTR emulation. The PDPTR
reserved bits are basically set in stone, and pushing a helper into
the MMU's calculation adds unnecessary complexity without improving
readability.
Oppurtunistically fix/update the comment for load_pdptrs().
Note, the buggy commit also introduced a deliberate functional change,
"Also remove bit 5-6 from rsvd_bits_mask per latest SDM.", which was
effectively (and correctly) reverted by commit cd9ae5fe47df ("KVM: x86:
Fix page-tables reserved bits"). A bit of SDM archaeology shows that
the SDM from late 2008 had a bug (likely a copy+paste error) where it
listed bits 6:5 as AVL and A for PDPTEs used for 4k entries but reserved
for 2mb entries. I.e. the SDM contradicted itself, and bits 6:5 are and
always have been reserved.
Fixes: 20c466b56168d ("KVM: Use rsvd_bits_mask in load_pdptrs()")
Cc: stable@vger.kernel.org
Cc: Nadav Amit <nadav.amit@gmail.com>
Reported-by: Doug Reiland <doug.reiland@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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We can easily route hardware interrupts directly into VM context when
they target the "Fixed" or "LowPriority" delivery modes.
However, on modes such as "SMI" or "Init", we need to go via KVM code
to actually put the vCPU into a different mode of operation, so we can
not post the interrupt
Add code in the VMX and SVM PI logic to explicitly refuse to establish
posted mappings for advanced IRQ deliver modes. This reflects the logic
in __apic_accept_irq() which also only ever passes Fixed and LowPriority
interrupts as posted interrupts into the guest.
This fixes a bug I have with code which configures real hardware to
inject virtual SMIs into my guest.
Signed-off-by: Alexander Graf <graf@amazon.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Wanpeng Li <wanpengli@tencent.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Add emulation (spoofing) of the SGDT, SIDT, and SMSW instructions for 64-bit
processes.
Wine users have encountered a number of 64-bit Windows games that use
these instructions (particularly SGDT), and were crashing when run on
UMIP-enabled systems.
Originally-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Brendan Shanks <bshanks@codeweavers.com>
Reviewed-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com>
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: Eric W. Biederman <ebiederm@xmission.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190905232222.14900-1-bshanks@codeweavers.com
[ Minor edits: capitalization, added 'spoofing' wording. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The RFC4106 key derivation code instantiates an AES cipher transform
to encrypt only a single block before it is freed again. Switch to
the new AES library which is more suitable for such use cases.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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KVM guests with commit c8c4076723da ("x86/timer: Skip PIT initialization on
modern chipsets") applied to guest kernel have been observed to have
unusually higher CPU usage with symptoms of increase in vm exits for HLT
and MSW_WRITE (MSR_IA32_TSCDEADLINE).
This is caused by older QEMUs lacking support for X86_FEATURE_ARAT. lapic
clock retains CLOCK_EVT_FEAT_C3STOP and nohz stays inactive. There's no
usable broadcast device either.
Do the PIT initialization if guest CPU lacks X86_FEATURE_ARAT. On real
hardware it shouldn't matter as ARAT and DEADLINE come together.
Fixes: c8c4076723da ("x86/timer: Skip PIT initialization on modern chipsets")
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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This reverts commit 558682b5291937a70748d36fd9ba757fb25b99ae.
Chris Wilson reports that it breaks his CPU hotplug test scripts. In
particular, it breaks offlining and then re-onlining the boot CPU, which
we treat specially (and the BIOS does too).
The symptoms are that we can offline the CPU, but it then does not come
back online again:
smpboot: CPU 0 is now offline
smpboot: Booting Node 0 Processor 0 APIC 0x0
smpboot: do_boot_cpu failed(-1) to wakeup CPU#0
Thomas says he knows why it's broken (my personal suspicion: our magic
handling of the "cpu0_logical_apicid" thing), but for 5.3 the right fix
is to just revert it, since we've never touched the LDR bits before, and
it's not worth the risk to do anything else at this stage.
[ Hotpluging of the boot CPU is special anyway, and should be off by
default. See the "BOOTPARAM_HOTPLUG_CPU0" config option and the
cpu0_hotplug kernel parameter.
In general you should not do it, and it has various known limitations
(hibernate and suspend require the boot CPU, for example).
But it should work, even if the boot CPU is special and needs careful
treatment - Linus ]
Link: https://lore.kernel.org/lkml/156785100521.13300.14461504732265570003@skylake-alporthouse-com/
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Bandan Das <bsd@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Boris suggests to make a local label (prepend ".L") to these functions
to eliminate them from the symbol table. These are functions with very
local names and really should not be visible anywhere.
Note that objtool won't see these functions anymore (to generate ORC
debug info). But all the functions are not annotated with ENDPROC, so
they won't have objtool's attention anyway.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Cao jin <caoj.fnst@cn.fujitsu.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steve Winslow <swinslow@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Huang <wei@redhat.com>
Cc: x86-ml <x86@kernel.org>
Cc: Xiaoyao Li <xiaoyao.li@linux.intel.com>
Link: https://lkml.kernel.org/r/20190906075550.23435-2-jslaby@suse.cz
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bogus_64_magic is only a dead-end loop. There is no need for an
out-of-order function (and unannotated local label), so just handle it
in-place and also store 0xbad-m-a-g-i-c to %rcx beforehand, in case
someone is inspecting registers.
Here a qemu+gdb example:
Remote debugging using localhost:1235
wakeup_long64 () at arch/x86/kernel/acpi/wakeup_64.S:26
26 jmp 1b
(gdb) info registers
rax 0x123456789abcdef0 1311768467463790320
rbx 0x0 0
rcx 0xbad6d61676963 3286910041024867
^^^^^^^^^^^^^^^
[ bp: Add the gdb example. ]
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Len Brown <lenb@kernel.org>
Cc: linux-pm@vger.kernel.org
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190906075550.23435-1-jslaby@suse.cz
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The last change to this Makefile caused relocation errors when loading
a kdump kernel. Restore -mcmodel=large (not -mcmodel=kernel),
-ffreestanding, and -fno-zero-initialized-bsss, without reverting to
the former practice of resetting KBUILD_CFLAGS.
Purgatory.ro is a standalone binary that is not linked against the
rest of the kernel. Its image is copied into an array that is linked
to the kernel, and from there kexec relocates it wherever it desires.
With the previous change to compiler flags, the error "kexec: Overflow
in relocation type 11 value 0x11fffd000" was encountered when trying
to load the crash kernel. This is from kexec code trying to relocate
the purgatory.ro object.
From the error message, relocation type 11 is R_X86_64_32S. The
x86_64 ABI says:
"The R_X86_64_32 and R_X86_64_32S relocations truncate the
computed value to 32-bits. The linker must verify that the
generated value for the R_X86_64_32 (R_X86_64_32S) relocation
zero-extends (sign-extends) to the original 64-bit value."
This type of relocation doesn't work when kexec chooses to place the
purgatory binary in memory that is not reachable with 32 bit
addresses.
The compiler flag -mcmodel=kernel allows those type of relocations to
be emitted, so revert to using -mcmodel=large as was done before.
Also restore the -ffreestanding and -fno-zero-initialized-bss flags
because they are appropriate for a stand alone piece of object code
which doesn't explicitly zero the bss, and one other report has said
undefined symbols are encountered without -ffreestanding.
These identical compiler flag changes need to happen for every object
that becomes part of the purgatory.ro object, so gather them together
first into PURGATORY_CFLAGS_REMOVE and PURGATORY_CFLAGS, and then
apply them to each of the objects that have C source. Do not apply
any of these flags to kexec-purgatory.o, which is not part of the
standalone object but part of the kernel proper.
Tested-by: Vaibhav Rustagi <vaibhavrustagi@google.com>
Tested-by: Andreas Smas <andreas@lonelycoder.com>
Signed-off-by: Steve Wahl <steve.wahl@hpe.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: None
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: clang-built-linux@googlegroups.com
Cc: dimitri.sivanich@hpe.com
Cc: mike.travis@hpe.com
Cc: russ.anderson@hpe.com
Fixes: b059f801a937 ("x86/purgatory: Use CFLAGS_REMOVE rather than reset KBUILD_CFLAGS")
Link: https://lkml.kernel.org/r/20190905202346.GA26595@swahl-linux
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The result of kmalloc() should have been checked ahead of below statement:
pqp = (struct bau_pq_entry *)vp;
Move BUG_ON(!vp) before above statement.
Signed-off-by: Austin Kim <austindh.kim@gmail.com>
Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Cc: Hedi Berriche <hedi.berriche@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Travis <mike.travis@hpe.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Cc: Steve Wahl <steve.wahl@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: allison@lohutok.net
Cc: andy@infradead.org
Cc: armijn@tjaldur.nl
Cc: bp@alien8.de
Cc: dvhart@infradead.org
Cc: gregkh@linuxfoundation.org
Cc: hpa@zytor.com
Cc: kjlu@umn.edu
Cc: platform-driver-x86@vger.kernel.org
Link: https://lkml.kernel.org/r/20190905232951.GA28779@LGEARND20B15
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Update properties for newly added Airmont CPU variant.
Signed-off-by: Rahul Tanwar <rahul.tanwar@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Gayatri Kammela <gayatri.kammela@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190905193020.14707-5-tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Add new Airmont variant CPU model to Intel family.
Signed-off-by: Rahul Tanwar <rahul.tanwar@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Gayatri Kammela <gayatri.kammela@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190905193020.14707-4-tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Add the model number/CPUID of atom based Elkhart Lake to the Intel
family.
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rahul Tanwar <rahul.tanwar@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190905193020.14707-3-tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Add the model numbers/CPUIDs of Tiger Lake mobile and desktop to the
Intel family.
Suggested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rahul Tanwar <rahul.tanwar@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190905193020.14707-2-tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Pull x86 fixes from Ingo Molnar:
"Misc fixes:
- EFI boot fix for signed kernels
- an AC flags fix related to UBSAN
- Hyper-V infinite loop fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/hyper-v: Fix overflow bug in fill_gva_list()
x86/uaccess: Don't leak the AC flags into __get_user() argument evaluation
x86/boot: Preserve boot_params.secure_boot from sanitizing
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When CONFIG_DEBUG_PER_CPU_MAPS=y we validate that the @node argument of
cpumask_of_node() is a valid node_id. It however forgets to check for
negative numbers. Fix this by explicitly casting to unsigned int.
(unsigned)node >= nr_node_ids
verifies: 0 <= node < nr_node_ids
Also ammend the error message to match the condition.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Yunsheng Lin <linyunsheng@huawei.com>
Link: https://lkml.kernel.org/r/20190903075352.GY2369@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The generic sha256 implementation from lib/crypto/sha256.c uses data
structs defined in crypto/sha.h, so lets move the function prototypes
there too.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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Rename static / file-local functions so that they do not conflict with
the functions declared in crypto/sha256.h.
This is a preparation patch for folding crypto/sha256.h into crypto/sha.h.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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Kbuild provides per-file compiler flag addition/removal:
CFLAGS_<basetarget>.o
CFLAGS_REMOVE_<basetarget>.o
AFLAGS_<basetarget>.o
AFLAGS_REMOVE_<basetarget>.o
CPPFLAGS_<basetarget>.lds
HOSTCFLAGS_<basetarget>.o
HOSTCXXFLAGS_<basetarget>.o
The <basetarget> is the filename of the target with its directory and
suffix stripped.
This syntax comes into a trouble when two files with the same basename
appear in one Makefile, for example:
obj-y += foo.o
obj-y += dir/foo.o
CFLAGS_foo.o := <some-flags>
Here, the <some-flags> applies to both foo.o and dir/foo.o
The real world problem is:
scripts/kconfig/util.c
scripts/kconfig/lxdialog/util.c
Both files are compiled into scripts/kconfig/mconf, but only the
latter should be given with the ncurses flags.
It is more sensible to use the relative path to the Makefile, like this:
obj-y += foo.o
CFLAGS_foo.o := <some-flags>
obj-y += dir/foo.o
CFLAGS_dir/foo.o := <other-flags>
At first, I attempted to replace $(basetarget) with $*. The $* variable
is replaced with the stem ('%') part in a pattern rule. This works with
most of cases, but does not for explicit rules.
For example, arch/ia64/lib/Makefile reuses rule_as_o_S in its own
explicit rules, so $* will be empty, resulting in ignoring the per-file
AFLAGS.
I introduced a new variable, target-stem, which can be used also from
explicit rules.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Marc Zyngier <maz@kernel.org>
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Most dma_map_ops instances are IOMMUs that work perfectly fine in 32-bits
of IOVA space, and the generic direct mapping code already provides its
own routines that is intelligent based on the amount of memory actually
present. Wire up the dma-direct routine for the ARM direct mapping code
as well, and otherwise default to the constant 32-bit mask. This way
we only need to override it for the occasional odd IOMMU that requires
64-bit IOVA support, or IOMMU drivers that are more efficient if they
can fall back to the direct mapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
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While the default ->mmap and ->get_sgtable implementations work for the
majority of our dma_map_ops impementations they are inherently safe
for others that don't use the page allocator or CMA and/or use their
own way of remapping not covered by the common code. So remove the
defaults if these methods are not wired up, but instead wire up the
default implementations for all safe instances.
Fixes: e1c7e324539a ("dma-mapping: always provide the dma_map_ops based implementation")
Signed-off-by: Christoph Hellwig <hch@lst.de>
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The AMD Ryzen gen 3 processors came with a different PCI IDs for the
function 3 & 4 which are used to access the SMN interface. The root
PCI address however remained at the same address as the model 30h.
Adding the F3/F4 PCI IDs respectively to the misc and link ids appear
to be sufficient for k10temp, so let's add them and follow up on the
patch if other functions need more tweaking.
Vicki Pfau sent an identical patch after I checked that no-one had
written this patch. I would have been happy about dropping my patch but
unlike for his patch series, I had already Cc:ed the x86 people and
they already reviewed the changes. Since Vicki has not answered to
any email after his initial series, let's assume she is on vacation
and let's avoid duplication of reviews from the maintainers and merge
my series. To acknowledge Vicki's anteriority, I added her S-o-b to
the patch.
v2, suggested by Guenter Roeck and Brian Woods:
- rename from 71h to 70h
Signed-off-by: Vicki Pfau <vi@endrift.com>
Signed-off-by: Marcel Bocu <marcel.p.bocu@gmail.com>
Tested-by: Marcel Bocu <marcel.p.bocu@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Brian Woods <brian.woods@amd.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> # pci_ids.h
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: x86@kernel.org
Cc: "Woods, Brian" <Brian.Woods@amd.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-hwmon@vger.kernel.org
Link: https://lore.kernel.org/r/20190722174510.2179-1-marcel.p.bocu@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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When cpus != maxcpus cpuidle-haltpoll will fail to register all vcpus
past the online ones and thus fail to register the idle driver.
This is because cpuidle_add_sysfs() will return with -ENODEV as a
consequence from get_cpu_device() return no device for a non-existing
CPU.
Instead switch to cpuidle_register_driver() and manually register each
of the present cpus through cpuhp_setup_state() callbacks and future
ones that get onlined or offlined. This mimmics similar logic that
intel_idle does.
Fixes: fa86ee90eb11 ("add cpuidle-haltpoll driver")
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.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>
Link: https://lkml.kernel.org/r/20190826075558.8125-5-hch@lst.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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These wrappers don't provide a real benefit over just using
set_memory_x() and set_memory_nx().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.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>
Link: https://lkml.kernel.org/r/20190826075558.8125-4-hch@lst.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.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>
Link: https://lkml.kernel.org/r/20190826075558.8125-3-hch@lst.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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No module currently messed with clearing or setting the execute
permission of kernel memory, and none really should.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.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>
Link: https://lkml.kernel.org/r/20190826075558.8125-2-hch@lst.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Signed-off-by: Ingo Molnar <mingo@kernel.org>
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When building with C=2, sparse makes note of a number of things:
arch/x86/events/intel/rapl.c:637:30: warning: symbol 'rapl_attr_update' was not declared. Should it be static?
arch/x86/events/intel/cstate.c:449:30: warning: symbol 'core_attr_update' was not declared. Should it be static?
arch/x86/events/intel/cstate.c:457:30: warning: symbol 'pkg_attr_update' was not declared. Should it be static?
arch/x86/events/msr.c:170:30: warning: symbol 'attr_update' was not declared. Should it be static?
arch/x86/events/intel/lbr.c:276:1: warning: symbol 'lbr_from_quirk_key' was not declared. Should it be static?
And they can all indeed be static.
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/128059.1565286242@turing-police
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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SD_BALANCE_{FORK,EXEC} and SD_WAKE_AFFINE are stripped in sd_init()
for any sched domains with a NUMA distance greater than 2 hops
(RECLAIM_DISTANCE). The idea being that it's expensive to balance
across domains that far apart.
However, as is rather unfortunately explained in:
commit 32e45ff43eaf ("mm: increase RECLAIM_DISTANCE to 30")
the value for RECLAIM_DISTANCE is based on node distance tables from
2011-era hardware.
Current AMD EPYC machines have the following NUMA node distances:
node distances:
node 0 1 2 3 4 5 6 7
0: 10 16 16 16 32 32 32 32
1: 16 10 16 16 32 32 32 32
2: 16 16 10 16 32 32 32 32
3: 16 16 16 10 32 32 32 32
4: 32 32 32 32 10 16 16 16
5: 32 32 32 32 16 10 16 16
6: 32 32 32 32 16 16 10 16
7: 32 32 32 32 16 16 16 10
where 2 hops is 32.
The result is that the scheduler fails to load balance properly across
NUMA nodes on different sockets -- 2 hops apart.
For example, pinning 16 busy threads to NUMA nodes 0 (CPUs 0-7) and 4
(CPUs 32-39) like so,
$ numactl -C 0-7,32-39 ./spinner 16
causes all threads to fork and remain on node 0 until the active
balancer kicks in after a few seconds and forcibly moves some threads
to node 4.
Override node_reclaim_distance for AMD Zen.
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Suravee.Suthikulpanit@amd.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas.Lendacky@amd.com
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20190808195301.13222-3-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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On x86_64 we can do a u64 * u64 -> u128 widening multiply followed by
a u128 / u64 -> u64 division to implement a sane version of
mul_u64_u32_div().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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After commit cf65a0f6f6ff ("dma-mapping: move all DMA mapping code to
kernel/dma") some of the files are referring to outdated information,
i.e. old file names of DMA mapping sources. Fix it here.
Note, the lines with "Glue code for..." have been removed completely.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Since x86 instruction decoder is not only for kprobes,
it should be tested when the insn.c is compiled.
(e.g. perf is enabled but kprobes is disabled)
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: cbe5c34c8c1f ("x86: Compile insn.c and inat.c only for KPROBES")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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When the 'start' parameter is >= 0xFF000000 on 32-bit
systems, or >= 0xFFFFFFFF'FF000000 on 64-bit systems,
fill_gva_list() gets into an infinite loop.
With such inputs, 'cur' overflows after adding HV_TLB_FLUSH_UNIT
and always compares as less than end. Memory is filled with
guest virtual addresses until the system crashes.
Fix this by never incrementing 'cur' to be larger than 'end'.
Reported-by: Jong Hyun Park <park.jonghyun@yonsei.ac.kr>
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 2ffd9e33ce4a ("x86/hyper-v: Use hypercall for remote TLB flush")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Identical to __put_user(); the __get_user() argument evalution will too
leak UBSAN crud into the __uaccess_begin() / __uaccess_end() region.
While uncommon this was observed to happen for:
drivers/xen/gntdev.c: if (__get_user(old_status, batch->status[i]))
where UBSAN added array bound checking.
This complements commit:
6ae865615fc4 ("x86/uaccess: Dont leak the AC flag into __put_user() argument evaluation")
Tested-by Sedat Dilek <sedat.dilek@gmail.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: broonie@kernel.org
Cc: sfr@canb.auug.org.au
Cc: akpm@linux-foundation.org
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: mhocko@suse.cz
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20190829082445.GM2369@hirez.programming.kicks-ass.net
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Correct spelling typos in comments in different files under arch/x86/.
[ bp: Merge into a single patch, massage. ]
Signed-off-by: Marco Ammon <marco.ammon@fau.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: trivial@kernel.org
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190902102436.27396-1-marco.ammon@fau.de
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Commit
a90118c445cc ("x86/boot: Save fields explicitly, zero out everything else")
now zeroes the secure boot setting information (enabled/disabled/...)
passed by the boot loader or by the kernel's EFI handover mechanism.
The problem manifests itself with signed kernels using the EFI handoff
protocol with grub and the kernel loses the information whether secure
boot is enabled in the firmware, i.e., the log message "Secure boot
enabled" becomes "Secure boot could not be determined".
efi_main() arch/x86/boot/compressed/eboot.c sets this field early but it
is subsequently zeroed by the above referenced commit.
Include boot_params.secure_boot in the preserve field list.
[ bp: restructure commit message and massage. ]
Fixes: a90118c445cc ("x86/boot: Save fields explicitly, zero out everything else")
Signed-off-by: John S. Gruber <JohnSGruber@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: stable <stable@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/CAPotdmSPExAuQcy9iAHqX3js_fc4mMLQOTr5RBGvizyCOPcTQQ@mail.gmail.com
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Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Conflicts:
tools/power/x86/turbostat/turbostat.c
Recent turbostat changes conflicted with a pending rename of x86 model names in tip:x86/cpu,
sort it out.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Pull x86 fixes from Thomas Gleixner:
"A set of fixes for x86:
- Fix the bogus detection of 32bit user mode for uretprobes which
caused corruption of the user return address resulting in
application crashes. In the uprobes handler in_ia32_syscall() is
obviously always returning false on a 64bit kernel. Use
user_64bit_mode() instead which works correctly.
- Prevent large page splitting when ftrace flips RW/RO on the kernel
text which caused iTLB performance issues. Ftrace wants to be
converted to text_poke() which avoids the problem, but for now
allow large page preservation in the static protections check when
the change request spawns a full large page.
- Prevent arch_dynirq_lower_bound() from returning 0 when the IOAPIC
is configured via device tree. In the device tree case the GSI 1:1
mapping is meaningless therefore the lower bound which protects the
GSI range on ACPI machines is irrelevant. Return the lower bound
which the core hands to the function instead of blindly returning 0
which causes the core to allocate the invalid virtual interupt
number 0 which in turn prevents all drivers from allocating and
requesting an interrupt.
- Remove the bogus initialization of LDR and DFR in the 32bit bigsmp
APIC driver. That uses physical destination mode where LDR/DFR are
ignored, but the initialization and the missing clear of LDR caused
the APIC to be left in a inconsistent state on kexec/reboot.
- Clear LDR when clearing the APIC registers so the APIC is in a well
defined state.
- Initialize variables proper in the find_trampoline_placement()
code.
- Silence GCC( build warning for the real mode part of the build"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm/cpa: Prevent large page split when ftrace flips RW on kernel text
x86/build: Add -Wnoaddress-of-packed-member to REALMODE_CFLAGS, to silence GCC9 build warning
x86/boot/compressed/64: Fix missing initialization in find_trampoline_placement()
x86/apic: Include the LDR when clearing out APIC registers
x86/apic: Do not initialize LDR and DFR for bigsmp
uprobes/x86: Fix detection of 32-bit user mode
x86/apic: Fix arch_dynirq_lower_bound() bug for DT enabled machines
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Pull perf fixes from Thomas Gleixner:
"Two fixes for perf x86 hardware implementations:
- Restrict the period on Nehalem machines to prevent perf from
hogging the CPU
- Prevent the AMD IBS driver from overwriting the hardwre controlled
and pre-seeded reserved bits (0-6) in the count register which
caused a sample bias for dispatched micro-ops"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/amd/ibs: Fix sample bias for dispatched micro-ops
perf/x86/intel: Restrict period on Nehalem
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Pull tracing fixes from Steven Rostedt:
"Small fixes and minor cleanups for tracing:
- Make exported ftrace function not static
- Fix NULL pointer dereference in reading probes as they are created
- Fix NULL pointer dereference in k/uprobe clean up path
- Various documentation fixes"
* tag 'trace-v5.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Correct kdoc formats
ftrace/x86: Remove mcount() declaration
tracing/probe: Fix null pointer dereference
tracing: Make exported ftrace_set_clr_event non-static
ftrace: Check for successful allocation of hash
ftrace: Check for empty hash and comment the race with registering probes
ftrace: Fix NULL pointer dereference in t_probe_next()
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Commit 562e14f72292 ("ftrace/x86: Remove mcount support") removed the
support for using mcount, so we could remove the mcount() declaration
to clean up.
Link: http://lkml.kernel.org/r/20190826170150.10f101ba@xhacker.debian
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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When counting dispatched micro-ops with cnt_ctl=1, in order to prevent
sample bias, IBS hardware preloads the least significant 7 bits of
current count (IbsOpCurCnt) with random values, such that, after the
interrupt is handled and counting resumes, the next sample taken
will be slightly perturbed.
The current count bitfield is in the IBS execution control h/w register,
alongside the maximum count field.
Currently, the IBS driver writes that register with the maximum count,
leaving zeroes to fill the current count field, thereby overwriting
the random bits the hardware preloaded for itself.
Fix the driver to actually retain and carry those random bits from the
read of the IBS control register, through to its write, instead of
overwriting the lower current count bits with zeroes.
Tested with:
perf record -c 100001 -e ibs_op/cnt_ctl=1/pp -a -C 0 taskset -c 0 <workload>
'perf annotate' output before:
15.70 65: addsd %xmm0,%xmm1
17.30 add $0x1,%rax
15.88 cmp %rdx,%rax
je 82
17.32 72: test $0x1,%al
jne 7c
7.52 movapd %xmm1,%xmm0
5.90 jmp 65
8.23 7c: sqrtsd %xmm1,%xmm0
12.15 jmp 65
'perf annotate' output after:
16.63 65: addsd %xmm0,%xmm1
16.82 add $0x1,%rax
16.81 cmp %rdx,%rax
je 82
16.69 72: test $0x1,%al
jne 7c
8.30 movapd %xmm1,%xmm0
8.13 jmp 65
8.24 7c: sqrtsd %xmm1,%xmm0
8.39 jmp 65
Tested on Family 15h and 17h machines.
Machines prior to family 10h Rev. C don't have the RDWROPCNT capability,
and have the IbsOpCurCnt bitfield reserved, so this patch shouldn't
affect their operation.
It is unknown why commit db98c5faf8cb ("perf/x86: Implement 64-bit
counter support for IBS") ignored the lower 4 bits of the IbsOpCurCnt
field; the number of preloaded random bits has always been 7, AFAICT.
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Arnaldo Carvalho de Melo" <acme@kernel.org>
Cc: <x86@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "Borislav Petkov" <bp@alien8.de>
Cc: Stephane Eranian <eranian@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: "Namhyung Kim" <namhyung@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20190826195730.30614-1-kim.phillips@amd.com
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We see our Nehalem machines reporting 'perfevents: irq loop stuck!' in
some cases when using perf:
perfevents: irq loop stuck!
WARNING: CPU: 0 PID: 3485 at arch/x86/events/intel/core.c:2282 intel_pmu_handle_irq+0x37b/0x530
...
RIP: 0010:intel_pmu_handle_irq+0x37b/0x530
...
Call Trace:
<NMI>
? perf_event_nmi_handler+0x2e/0x50
? intel_pmu_save_and_restart+0x50/0x50
perf_event_nmi_handler+0x2e/0x50
nmi_handle+0x6e/0x120
default_do_nmi+0x3e/0x100
do_nmi+0x102/0x160
end_repeat_nmi+0x16/0x50
...
? native_write_msr+0x6/0x20
? native_write_msr+0x6/0x20
</NMI>
intel_pmu_enable_event+0x1ce/0x1f0
x86_pmu_start+0x78/0xa0
x86_pmu_enable+0x252/0x310
__perf_event_task_sched_in+0x181/0x190
? __switch_to_asm+0x41/0x70
? __switch_to_asm+0x35/0x70
? __switch_to_asm+0x41/0x70
? __switch_to_asm+0x35/0x70
finish_task_switch+0x158/0x260
__schedule+0x2f6/0x840
? hrtimer_start_range_ns+0x153/0x210
schedule+0x32/0x80
schedule_hrtimeout_range_clock+0x8a/0x100
? hrtimer_init+0x120/0x120
ep_poll+0x2f7/0x3a0
? wake_up_q+0x60/0x60
do_epoll_wait+0xa9/0xc0
__x64_sys_epoll_wait+0x1a/0x20
do_syscall_64+0x4e/0x110
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fdeb1e96c03
...
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: acme@kernel.org
Cc: Josh Hunt <johunt@akamai.com>
Cc: bpuranda@akamai.com
Cc: mingo@redhat.com
Cc: jolsa@redhat.com
Cc: tglx@linutronix.de
Cc: namhyung@kernel.org
Cc: alexander.shishkin@linux.intel.com
Link: https://lkml.kernel.org/r/1566256411-18820-1-git-send-email-johunt@akamai.com
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When PTI is disabled at boot time either because the CPU is not affected or
PTI has been disabled on the command line, the boot code still calls into
pti_finalize() which then unconditionally invokes:
pti_clone_entry_text()
pti_clone_kernel_text()
pti_clone_kernel_text() was called unconditionally before the 32bit support
was added and 32bit added the call to pti_clone_entry_text().
The call has no side effects as cloning the page tables into the available
second one, which was allocated for PTI does not create damage. But it does
not make sense either and in case that this functionality would be extended
later this might actually lead to hard to diagnose issues.
Neither function should be called when PTI is runtime disabled. Make the
invocation conditional.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190828143124.063353972@linutronix.de
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pti_clone_pmds() assumes that the supplied address is either:
- properly PUD/PMD aligned
or
- the address is actually mapped which means that independently
of the mapping level (PUD/PMD/PTE) the next higher mapping
exists.
If that's not the case the unaligned address can be incremented by PUD or
PMD size incorrectly. All callers supply mapped and/or aligned addresses,
but for the sake of robustness it's better to handle that case properly and
to emit a warning.
[ tglx: Rewrote changelog and added WARN_ON_ONCE() ]
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1908282352470.1938@nanos.tec.linutronix.de
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ftrace does not use text_poke() for enabling trace functionality. It uses
its own mechanism and flips the whole kernel text to RW and back to RO.
The CPA rework removed a loop based check of 4k pages which tried to
preserve a large page by checking each 4k page whether the change would
actually cover all pages in the large page.
This resulted in endless loops for nothing as in testing it turned out that
it actually never preserved anything. Of course testing missed to include
ftrace, which is the one and only case which benefitted from the 4k loop.
As a consequence enabling function tracing or ftrace based kprobes results
in a full 4k split of the kernel text, which affects iTLB performance.
The kernel RO protection is the only valid case where this can actually
preserve large pages.
All other static protections (RO data, data NX, PCI, BIOS) are truly
static. So a conflict with those protections which results in a split
should only ever happen when a change of memory next to a protected region
is attempted. But these conflicts are rightfully splitting the large page
to preserve the protected regions. In fact a change to the protected
regions itself is a bug and is warned about.
Add an exception for the static protection check for kernel text RO when
the to be changed region spawns a full large page which allows to preserve
the large mappings. This also prevents the syslog to be spammed about CPA
violations when ftrace is used.
The exception needs to be removed once ftrace switched over to text_poke()
which avoids the whole issue.
Fixes: 585948f4f695 ("x86/mm/cpa: Avoid the 4k pages check completely")
Reported-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Song Liu <songliubraving@fb.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1908282355340.1938@nanos.tec.linutronix.de
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Sean Christopherson
Alexander Graf
Brendan Shanks
Ard Biesheuvel
Jan Stancek
Linus Torvalds
Jiri Slaby
Steve Wahl
Austin Kim
Ingo Molnar
Rahul Tanwar
Gayatri Kammela
Peter Zijlstra
Hans de Goede
Masahiro Yamada
Christoph Hellwig
Marcel Bocu
Joao Martins
Valdis Klētnieks
Matt Fleming
Andy Shevchenko
Masami Hiramatsu
Tianyu Lan
Marco Ammon
John S. Gruber
Jisheng Zhang
Kim Phillips
Josh Hunt
Thomas Gleixner
Song Liu