Commit Graph

37638 Commits

Author SHA1 Message Date
Gaurav Kohli
22c1d8f24c x86/hyperv: Remove unregister syscore call from Hyper-V cleanup
[ Upstream commit 32c97d980e2eef25465d453f2956a9ca68926a3c ]

Hyper-V cleanup code comes under panic path where preemption and irq
is already disabled. So calling of unregister_syscore_ops might schedule
out the thread even for the case where mutex lock is free.
hyperv_cleanup
	unregister_syscore_ops
			mutex_lock(&syscore_ops_lock)
				might_sleep
Here might_sleep might schedule out this thread, where voluntary preemption
config is on and this thread will never comes back. And also this was added
earlier to maintain the symmetry which is not required as this can comes
during crash shutdown path only.

To prevent the same, removing unregister_syscore_ops function call.

Signed-off-by: Gaurav Kohli <gauravkohli@linux.microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1669443291-2575-1-git-send-email-gauravkohli@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14 10:16:13 +01:00
Xiu Jianfeng
70e7f308d7 x86/xen: Fix memory leak in xen_init_lock_cpu()
[ Upstream commit ca84ce153d887b1dc8b118029976cc9faf2a9b40 ]

In xen_init_lock_cpu(), the @name has allocated new string by kasprintf(),
if bind_ipi_to_irqhandler() fails, it should be freed, otherwise may lead
to a memory leak issue, fix it.

Fixes: 2d9e1e2f58 ("xen: implement Xen-specific spinlocks")
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20221123155858.11382-3-xiujianfeng@huawei.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14 10:15:21 +01:00
Xiu Jianfeng
fc134c355b x86/xen: Fix memory leak in xen_smp_intr_init{_pv}()
[ Upstream commit 69143f60868b3939ddc89289b29db593b647295e ]

These local variables @{resched|pmu|callfunc...}_name saves the new
string allocated by kasprintf(), and when bind_{v}ipi_to_irqhandler()
fails, it goes to the @fail tag, and calls xen_smp_intr_free{_pv}() to
free resource, however the new string is not saved, which cause a memory
leak issue. fix it.

Fixes: 9702785a74 ("i386: move xen")
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20221123155858.11382-2-xiujianfeng@huawei.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14 10:15:21 +01:00
Oleg Nesterov
95dbcb7e1c uprobes/x86: Allow to probe a NOP instruction with 0x66 prefix
[ Upstream commit cefa72129e45313655d53a065b8055aaeb01a0c9 ]

Intel ICC -hotpatch inserts 2-byte "0x66 0x90" NOP at the start of each
function to reserve extra space for hot-patching, and currently it is not
possible to probe these functions because branch_setup_xol_ops() wrongly
rejects NOP with REP prefix as it treats them like word-sized branch
instructions.

Fixes: 250bbd12c2 ("uprobes/x86: Refuse to attach uprobe to "word-sized" branch insns")
Reported-by: Seiji Nishikawa <snishika@redhat.com>
Suggested-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20221204173933.GA31544@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14 10:15:21 +01:00
Xiongfeng Wang
0afcb759f6 perf/x86/intel/uncore: Fix reference count leak in __uncore_imc_init_box()
[ Upstream commit 17b8d847b92d815d1638f0de154654081d66b281 ]

pci_get_device() will increase the reference count for the returned
pci_dev, so tgl_uncore_get_mc_dev() will return a pci_dev with its
reference count increased. We need to call pci_dev_put() to decrease the
reference count before exiting from __uncore_imc_init_box(). Add
pci_dev_put() for both normal and error path.

Fixes: fdb6482244 ("perf/x86: Add Intel Tiger Lake uncore support")
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20221118063137.121512-5-wangxiongfeng2@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14 10:15:18 +01:00
Xiongfeng Wang
d2afced511 perf/x86/intel/uncore: Fix reference count leak in snr_uncore_mmio_map()
[ Upstream commit 8ebd16c11c346751b3944d708e6c181ed4746c39 ]

pci_get_device() will increase the reference count for the returned
pci_dev, so snr_uncore_get_mc_dev() will return a pci_dev with its
reference count increased. We need to call pci_dev_put() to decrease the
reference count. Let's add the missing pci_dev_put().

Fixes: ee49532b38 ("perf/x86/intel/uncore: Add IMC uncore support for Snow Ridge")
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20221118063137.121512-4-wangxiongfeng2@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14 10:15:17 +01:00
Xiongfeng Wang
c0539d5d47 perf/x86/intel/uncore: Fix reference count leak in hswep_has_limit_sbox()
[ Upstream commit 1ff9dd6e7071a561f803135c1d684b13c7a7d01d ]

pci_get_device() will increase the reference count for the returned
'dev'. We need to call pci_dev_put() to decrease the reference count.
Since 'dev' is only used in pci_read_config_dword(), let's add
pci_dev_put() right after it.

Fixes: 9d480158ee86 ("perf/x86/intel/uncore: Remove uncore extra PCI dev HSWEP_PCI_PCU_3")
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20221118063137.121512-3-wangxiongfeng2@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14 10:15:17 +01:00
Stefan Metzmacher
f0a5f0dc01 x86/process: setup io_threads more like normal user space threads
[ Upstream commit 50b7b6f29de3e18e9d6c09641256a0296361cfee ]

As io_threads are fully set up USER threads it's clearer to separate the
code path from the KTHREAD logic.

The only remaining difference to user space threads is that io_threads
never return to user space again. Instead they loop within the given
worker function.

The fact that they never return to user space means they don't have an
user space thread stack. In order to indicate that to tools like gdb we
reset the stack and instruction pointers to 0.

This allows gdb attach to user space processes using io-uring, which like
means that they have io_threads, without printing worrying message like
this:

  warning: Selected architecture i386:x86-64 is not compatible with reported target architecture i386

  warning: Architecture rejected target-supplied description

The output will be something like this:

  (gdb) info threads
    Id   Target Id                  Frame
  * 1    LWP 4863 "io_uring-cp-for" syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
    2    LWP 4864 "iou-mgr-4863"    0x0000000000000000 in ?? ()
    3    LWP 4865 "iou-wrk-4863"    0x0000000000000000 in ?? ()
  (gdb) thread 3
  [Switching to thread 3 (LWP 4865)]
  #0  0x0000000000000000 in ?? ()
  (gdb) bt
  #0  0x0000000000000000 in ?? ()
  Backtrace stopped: Cannot access memory at address 0x0

Fixes: 4727dc20e042 ("arch: setup PF_IO_WORKER threads like PF_KTHREAD")
Link: https://lore.kernel.org/io-uring/044d0bad-6888-a211-e1d3-159a4aeed52d@polymtl.ca/T/#m1bbf5727e3d4e839603f6ec7ed79c7eebfba6267
Signed-off-by: Stefan Metzmacher <metze@samba.org>
cc: Linus Torvalds <torvalds@linux-foundation.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: Andy Lutomirski <luto@kernel.org>
cc: linux-kernel@vger.kernel.org
cc: io-uring@vger.kernel.org
cc: x86@kernel.org
Link: https://lore.kernel.org/r/20210505110310.237537-1-metze@samba.org
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-04 11:39:23 +01:00
Jens Axboe
320c8057ec arch: setup PF_IO_WORKER threads like PF_KTHREAD
[ Upstream commit 4727dc20e0422211a0e0c72b1ace4ed6096df8a6 ]

PF_IO_WORKER are kernel threads too, but they aren't PF_KTHREAD in the
sense that we don't assign ->set_child_tid with our own structure. Just
ensure that every arch sets up the PF_IO_WORKER threads like kthreads
in the arch implementation of copy_thread().

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-04 11:39:22 +01:00
Jens Axboe
4b1dcf8ec9 x86: Wire up TIF_NOTIFY_SIGNAL
[ Upstream commit c8d5ed67936fddbe2ae845fc80397718006322d7 ]

The generic entry code has support for TIF_NOTIFY_SIGNAL already. Just
provide the TIF bit.

[ tglx: Adopted to other TIF changes in x86 ]

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201026203230.386348-4-axboe@kernel.dk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-04 11:39:18 +01:00
Jens Axboe
3c295bd2dd entry: Add support for TIF_NOTIFY_SIGNAL
[ Upstream commit 12db8b690010ccfadf9d0b49a1e1798e47dbbe1a ]

Add TIF_NOTIFY_SIGNAL handling in the generic entry code, which if set,
will return true if signal_pending() is used in a wait loop. That causes an
exit of the loop so that notify_signal tracehooks can be run. If the wait
loop is currently inside a system call, the system call is restarted once
task_work has been processed.

In preparation for only having arch_do_signal() handle syscall restarts if
_TIF_SIGPENDING isn't set, rename it to arch_do_signal_or_restart().  Pass
in a boolean that tells the architecture specific signal handler if it
should attempt to get a signal, or just process a potential syscall
restart.

For !CONFIG_GENERIC_ENTRY archs, add the TIF_NOTIFY_SIGNAL handling to
get_signal(). This is done to minimize the needed architecture changes to
support this feature.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20201026203230.386348-3-axboe@kernel.dk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-04 11:39:18 +01:00
Paul E. McKenney
970862a96c x86/smpboot: Move rcu_cpu_starting() earlier
commit 29368e09392123800e5e2bf0f3eda91f16972e52 upstream.

The call to rcu_cpu_starting() in mtrr_ap_init() is not early enough
in the CPU-hotplug onlining process, which results in lockdep splats
as follows:

=============================
WARNING: suspicious RCU usage
5.9.0+ #268 Not tainted
-----------------------------
kernel/kprobes.c:300 RCU-list traversed in non-reader section!!

other info that might help us debug this:

RCU used illegally from offline CPU!
rcu_scheduler_active = 1, debug_locks = 1
no locks held by swapper/1/0.

stack backtrace:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0+ #268
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-1ubuntu1 04/01/2014
Call Trace:
 dump_stack+0x77/0x97
 __is_insn_slot_addr+0x15d/0x170
 kernel_text_address+0xba/0xe0
 ? get_stack_info+0x22/0xa0
 __kernel_text_address+0x9/0x30
 show_trace_log_lvl+0x17d/0x380
 ? dump_stack+0x77/0x97
 dump_stack+0x77/0x97
 __lock_acquire+0xdf7/0x1bf0
 lock_acquire+0x258/0x3d0
 ? vprintk_emit+0x6d/0x2c0
 _raw_spin_lock+0x27/0x40
 ? vprintk_emit+0x6d/0x2c0
 vprintk_emit+0x6d/0x2c0
 printk+0x4d/0x69
 start_secondary+0x1c/0x100
 secondary_startup_64_no_verify+0xb8/0xbb

This is avoided by moving the call to rcu_cpu_starting up near
the beginning of the start_secondary() function.  Note that the
raw_smp_processor_id() is required in order to avoid calling into lockdep
before RCU has declared the CPU to be watched for readers.

Link: https://lore.kernel.org/lkml/160223032121.7002.1269740091547117869.tip-bot2@tip-bot2/
Reported-by: Qian Cai <cai@redhat.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Joel Fernandes <joel@joelfernandes.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-19 12:27:30 +01:00
Mateusz Jończyk
775d4661f1 rtc: Check return value from mc146818_get_time()
[ Upstream commit 0dd8d6cb9eddfe637bcd821bbfd40ebd5a0737b9 ]

There are 4 users of mc146818_get_time() and none of them was checking
the return value from this function. Change this.

Print the appropriate warnings in callers of mc146818_get_time() instead
of in the function mc146818_get_time() itself, in order not to add
strings to rtc-mc146818-lib.c, which is kind of a library.

The callers of alpha_rtc_read_time() and cmos_read_time() may use the
contents of (struct rtc_time *) even when the functions return a failure
code. Therefore, set the contents of (struct rtc_time *) to 0x00,
which looks more sensible then 0xff and aligns with the (possibly
stale?) comment in cmos_read_time:

	/*
	 * If pm_trace abused the RTC for storage, set the timespec to 0,
	 * which tells the caller that this RTC value is unusable.
	 */

For consistency, do this in mc146818_get_time().

Note: hpet_rtc_interrupt() may call mc146818_get_time() many times a
second. It is very unlikely, though, that the RTC suddenly stops
working and mc146818_get_time() would consistently fail.

Only compile-tested on alpha.

Signed-off-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: linux-alpha@vger.kernel.org
Cc: x86@kernel.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211210200131.153887-4-mat.jonczyk@o2.pl
Stable-dep-of: cd17420ebea5 ("rtc: cmos: avoid UIP when writing alarm time")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-14 11:31:55 +01:00
Pawan Gupta
7462cd2443 x86/pm: Add enumeration check before spec MSRs save/restore setup
commit 50bcceb7724e471d9b591803889df45dcbb584bc upstream.

pm_save_spec_msr() keeps a list of all the MSRs which _might_ need
to be saved and restored at hibernate and resume. However, it has
zero awareness of CPU support for these MSRs. It mostly works by
unconditionally attempting to manipulate these MSRs and relying on
rdmsrl_safe() being able to handle a #GP on CPUs where the support is
unavailable.

However, it's possible for reads (RDMSR) to be supported for a given MSR
while writes (WRMSR) are not. In this case, msr_build_context() sees
a successful read (RDMSR) and marks the MSR as valid. Then, later, a
write (WRMSR) fails, producing a nasty (but harmless) error message.
This causes restore_processor_state() to try and restore it, but writing
this MSR is not allowed on the Intel Atom N2600 leading to:

  unchecked MSR access error: WRMSR to 0x122 (tried to write 0x0000000000000002) \
     at rIP: 0xffffffff8b07a574 (native_write_msr+0x4/0x20)
  Call Trace:
   <TASK>
   restore_processor_state
   x86_acpi_suspend_lowlevel
   acpi_suspend_enter
   suspend_devices_and_enter
   pm_suspend.cold
   state_store
   kernfs_fop_write_iter
   vfs_write
   ksys_write
   do_syscall_64
   ? do_syscall_64
   ? up_read
   ? lock_is_held_type
   ? asm_exc_page_fault
   ? lockdep_hardirqs_on
   entry_SYSCALL_64_after_hwframe

To fix this, add the corresponding X86_FEATURE bit for each MSR.  Avoid
trying to manipulate the MSR when the feature bit is clear. This
required adding a X86_FEATURE bit for MSRs that do not have one already,
but it's a small price to pay.

  [ bp: Move struct msr_enumeration inside the only function that uses it. ]
  [Pawan: Resolve build issue in backport]

Fixes: 73924ec4d560 ("x86/pm: Save the MSR validity status at context setup")
Reported-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/c24db75d69df6e66c0465e13676ad3f2837a2ed8.1668539735.git.pawan.kumar.gupta@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:23:59 +01:00
Pawan Gupta
5e3d4a68e2 x86/tsx: Add a feature bit for TSX control MSR support
commit aaa65d17eec372c6a9756833f3964ba05b05ea14 upstream.

Support for the TSX control MSR is enumerated in MSR_IA32_ARCH_CAPABILITIES.
This is different from how other CPU features are enumerated i.e. via
CPUID. Currently, a call to tsx_ctrl_is_supported() is required for
enumerating the feature. In the absence of a feature bit for TSX control,
any code that relies on checking feature bits directly will not work.

In preparation for adding a feature bit check in MSR save/restore
during suspend/resume, set a new feature bit X86_FEATURE_TSX_CTRL when
MSR_IA32_TSX_CTRL is present.

  [ bp: Remove tsx_ctrl_is_supported()]

  [Pawan: Resolved conflicts in backport; Removed parts of commit message
          referring to removed function tsx_ctrl_is_supported()]

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/de619764e1d98afbb7a5fa58424f1278ede37b45.1668539735.git.pawan.kumar.gupta@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:23:59 +01:00
Pawan Gupta
471fb7b735 x86/bugs: Make sure MSR_SPEC_CTRL is updated properly upon resume from S3
commit 66065157420c5b9b3f078f43d313c153e1ff7f83 upstream.

The "force" argument to write_spec_ctrl_current() is currently ambiguous
as it does not guarantee the MSR write. This is due to the optimization
that writes to the MSR happen only when the new value differs from the
cached value.

This is fine in most cases, but breaks for S3 resume when the cached MSR
value gets out of sync with the hardware MSR value due to S3 resetting
it.

When x86_spec_ctrl_current is same as x86_spec_ctrl_base, the MSR write
is skipped. Which results in SPEC_CTRL mitigations not getting restored.

Move the MSR write from write_spec_ctrl_current() to a new function that
unconditionally writes to the MSR. Update the callers accordingly and
rename functions.

  [ bp: Rework a bit. ]

Fixes: caa0ff24d5d0 ("x86/bugs: Keep a per-CPU IA32_SPEC_CTRL value")
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/806d39b0bfec2fe8f50dc5446dff20f5bb24a959.1669821572.git.pawan.kumar.gupta@linux.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:23:57 +01:00
Michael Kelley
22870431cd x86/ioremap: Fix page aligned size calculation in __ioremap_caller()
commit 4dbd6a3e90e03130973688fd79e19425f720d999 upstream.

Current code re-calculates the size after aligning the starting and
ending physical addresses on a page boundary. But the re-calculation
also embeds the masking of high order bits that exceed the size of
the physical address space (via PHYSICAL_PAGE_MASK). If the masking
removes any high order bits, the size calculation results in a huge
value that is likely to immediately fail.

Fix this by re-calculating the page-aligned size first. Then mask any
high order bits using PHYSICAL_PAGE_MASK.

Fixes: ffa71f33a8 ("x86, ioremap: Fix incorrect physical address handling in PAE mode")
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/1668624097-14884-2-git-send-email-mikelley@microsoft.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-02 17:40:04 +01:00
Maxim Levitsky
3fdeacf087 KVM: x86: remove exit_int_info warning in svm_handle_exit
commit 05311ce954aebe75935d9ae7d38ac82b5b796e33 upstream.

It is valid to receive external interrupt and have broken IDT entry,
which will lead to #GP with exit_int_into that will contain the index of
the IDT entry (e.g any value).

Other exceptions can happen as well, like #NP or #SS
(if stack switch fails).

Thus this warning can be user triggred and has very little value.

Cc: stable@vger.kernel.org
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20221103141351.50662-10-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-02 17:40:04 +01:00
Maxim Levitsky
7e5cb13091 KVM: x86: nSVM: leave nested mode on vCPU free
commit 917401f26a6af5756d89b550a8e1bd50cf42b07e upstream.

If the VM was terminated while nested, we free the nested state
while the vCPU still is in nested mode.

Soon a warning will be added for this condition.

Cc: stable@vger.kernel.org
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20221103141351.50662-2-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-02 17:40:04 +01:00
Adrian Hunter
5e2f14d772 perf/x86/intel/pt: Fix sampling using single range output
commit ce0d998be9274dd3a3d971cbeaa6fe28fd2c3062 upstream.

Deal with errata TGL052, ADL037 and RPL017 "Trace May Contain Incorrect
Data When Configured With Single Range Output Larger Than 4KB" by
disabling single range output whenever larger than 4KB.

Fixes: 670638477a ("perf/x86/intel/pt: Opportunistically use single range output mode")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20221112151508.13768-1-adrian.hunter@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25 17:45:54 +01:00
Borislav Petkov
154d744fbe x86/cpu: Restore AMD's DE_CFG MSR after resume
commit 2632daebafd04746b4b96c2f26a6021bc38f6209 upstream.

DE_CFG contains the LFENCE serializing bit, restore it on resume too.
This is relevant to older families due to the way how they do S3.

Unify and correct naming while at it.

Fixes: e4d0e84e49 ("x86/cpu/AMD: Make LFENCE a serializing instruction")
Reported-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Reported-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-16 09:57:20 +01:00
Maxim Levitsky
e5cef906cb KVM: x86: emulator: update the emulation mode after CR0 write
commit ad8f9e69942c7db90758d9d774157e53bce94840 upstream.

Update the emulation mode when handling writes to CR0, because
toggling CR0.PE switches between Real and Protected Mode, and toggling
CR0.PG when EFER.LME=1 switches between Long and Protected Mode.

This is likely a benign bug because there is no writeback of state,
other than the RIP increment, and when toggling CR0.PE, the CPU has
to execute code from a very low memory address.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20221025124741.228045-14-mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:29 +01:00
Maxim Levitsky
ce9261accc KVM: x86: emulator: introduce emulator_recalc_and_set_mode
commit d087e0f79fa0dd336a9a6b2f79ec23120f5eff73 upstream.

Some instructions update the cpu execution mode, which needs to update the
emulation mode.

Extract this code, and make assign_eip_far use it.

assign_eip_far now reads CS, instead of getting it via a parameter,
which is ok, because callers always assign CS to the same value
before calling this function.

No functional change is intended.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20221025124741.228045-12-mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:28 +01:00
Maxim Levitsky
c8a2fd7a71 KVM: x86: emulator: em_sysexit should update ctxt->mode
commit 5015bb89b58225f97df6ac44383e7e8c8662c8c9 upstream.

SYSEXIT is one of the instructions that can change the
processor mode, thus ctxt->mode should be updated after it.

Note that this is likely a benign bug, because the only problematic
mode change is from 32 bit to 64 bit which can lead to truncation of RIP,
and it is not possible to do with sysexit,
since sysexit running in 32 bit mode will be limited to 32 bit version.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20221025124741.228045-11-mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:28 +01:00
Jim Mattson
e0c7410378 KVM: x86: Mask off reserved bits in CPUID.80000001H
commit 0469e56a14bf8cfb80507e51b7aeec0332cdbc13 upstream.

KVM_GET_SUPPORTED_CPUID should only enumerate features that KVM
actually supports. CPUID.80000001:EBX[27:16] are reserved bits and
should be masked off.

Fixes: 0771671749 ("KVM: Enhance guest cpuid management")
Signed-off-by: Jim Mattson <jmattson@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:28 +01:00
Jim Mattson
9302ebc1c2 KVM: x86: Mask off reserved bits in CPUID.80000008H
commit 7030d8530e533844e2f4b0e7476498afcd324634 upstream.

KVM_GET_SUPPORTED_CPUID should only enumerate features that KVM
actually supports. The following ranges of CPUID.80000008H are reserved
and should be masked off:
    ECX[31:18]
    ECX[11:8]

In addition, the PerfTscSize field at ECX[17:16] should also be zero
because KVM does not set the PERFTSC bit at CPUID.80000001H.ECX[27].

Fixes: 24c82e576b ("KVM: Sanitize cpuid")
Signed-off-by: Jim Mattson <jmattson@google.com>
Message-Id: <20220929225203.2234702-3-jmattson@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:28 +01:00
Jim Mattson
cc40c5f3e9 KVM: x86: Mask off reserved bits in CPUID.8000001AH
commit 079f6889818dd07903fb36c252532ab47ebb6d48 upstream.

KVM_GET_SUPPORTED_CPUID should only enumerate features that KVM
actually supports. In the case of CPUID.8000001AH, only three bits are
currently defined. The 125 reserved bits should be masked off.

Fixes: 24c82e576b ("KVM: Sanitize cpuid")
Signed-off-by: Jim Mattson <jmattson@google.com>
Message-Id: <20220929225203.2234702-4-jmattson@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:28 +01:00
Jim Mattson
bd64a88f36 KVM: x86: Mask off reserved bits in CPUID.80000006H
commit eeb69eab57c6604ac90b3fd8e5ac43f24a5535b1 upstream.

KVM_GET_SUPPORTED_CPUID should only enumerate features that KVM
actually supports. CPUID.80000006H:EDX[17:16] are reserved bits and
should be masked off.

Fixes: 43d05de2be ("KVM: pass through CPUID(0x80000006)")
Signed-off-by: Jim Mattson <jmattson@google.com>
Message-Id: <20220929225203.2234702-2-jmattson@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:28 +01:00
Kan Liang
29d106d086 perf/x86/intel: Add Cooper Lake stepping to isolation_ucodes[]
commit 6f8faf471446844bb9c318e0340221049d5c19f4 upstream.

The intel_pebs_isolation quirk checks both model number and stepping.
Cooper Lake has a different stepping (11) than the other Skylake Xeon.
It cannot benefit from the optimization in commit 9b545c04ab
("perf/x86/kvm: Avoid unnecessary work in guest filtering").

Add the stepping of Cooper Lake into the isolation_ucodes[] table.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20221031154550.571663-1-kan.liang@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:27 +01:00
Kan Liang
98f6e7c337 perf/x86/intel: Fix pebs event constraints for ICL
commit acc5568b90c19ac6375508a93b9676cd18a92a35 upstream.

According to the latest event list, update the MEM_INST_RETIRED events
which support the DataLA facility.

Fixes: 6017608936 ("perf/x86/intel: Add Icelake support")
Reported-by: Jannis Klinkenberg <jannis.klinkenberg@rwth-aachen.de>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20221031154119.571386-1-kan.liang@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:27 +01:00
Alexander Graf
4dbb739eb2 KVM: x86: Add compat handler for KVM_X86_SET_MSR_FILTER
[ Upstream commit 1739c7017fb1d759965dcbab925ff5980a5318cb ]

The KVM_X86_SET_MSR_FILTER ioctls contains a pointer in the passed in
struct which means it has a different struct size depending on whether
it gets called from 32bit or 64bit code.

This patch introduces compat code that converts from the 32bit struct to
its 64bit counterpart which then gets used going forward internally.
With this applied, 32bit QEMU can successfully set MSR bitmaps when
running on 64bit kernels.

Reported-by: Andrew Randrianasulu <randrianasulu@gmail.com>
Fixes: 1a155254ff ("KVM: x86: Introduce MSR filtering")
Signed-off-by: Alexander Graf <graf@amazon.com>
Message-Id: <20221017184541.2658-4-graf@amazon.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:15 +01:00
Alexander Graf
bb584caee8 KVM: x86: Copy filter arg outside kvm_vm_ioctl_set_msr_filter()
[ Upstream commit 2e3272bc1790825c43d2c39690bf2836b81c6d36 ]

In the next patch we want to introduce a second caller to
set_msr_filter() which constructs its own filter list on the stack.
Refactor the original function so it takes it as argument instead of
reading it through copy_from_user().

Signed-off-by: Alexander Graf <graf@amazon.com>
Message-Id: <20221017184541.2658-3-graf@amazon.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:15 +01:00
Aaron Lewis
9faacf442d KVM: x86: Protect the unused bits in MSR exiting flags
[ Upstream commit cf5029d5dd7cb0aaa53250fa9e389abd231606b3 ]

The flags for KVM_CAP_X86_USER_SPACE_MSR and KVM_X86_SET_MSR_FILTER
have no protection for their unused bits.  Without protection, future
development for these features will be difficult.  Add the protection
needed to make it possible to extend these features in the future.

Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Message-Id: <20220714161314.1715227-1-aaronlewis@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: 2e3272bc1790 ("KVM: x86: Copy filter arg outside kvm_vm_ioctl_set_msr_filter()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:15 +01:00
Zhang Rui
5bdbccc79c x86/topology: Fix duplicated core ID within a package
[ Upstream commit 71eac7063698b7d7b8fafb1683ac24a034541141 ]

Today, core ID is assumed to be unique within each package.

But an AlderLake-N platform adds a Module level between core and package,
Linux excludes the unknown modules bits from the core ID, resulting in
duplicate core ID's.

To keep core ID unique within a package, Linux must include all APIC-ID
bits for known or unknown levels above the core and below the package
in the core ID.

It is important to understand that core ID's have always come directly
from the APIC-ID encoding, which comes from the BIOS. Thus there is no
guarantee that they start at 0, or that they are contiguous.
As such, naively using them for array indexes can be problematic.

[ dhansen: un-known -> unknown ]

Fixes: 7745f03eb3 ("x86/topology: Add CPUID.1F multi-die/package support")
Suggested-by: Len Brown <len.brown@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Len Brown <len.brown@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20221014090147.1836-5-rui.zhang@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:15 +01:00
Zhang Rui
6c31fc028a x86/topology: Fix multiple packages shown on a single-package system
[ Upstream commit 2b12a7a126d62bdbd81f4923c21bf6e9a7fbd069 ]

CPUID.1F/B does not enumerate Package level explicitly, instead, all the
APIC-ID bits above the enumerated levels are assumed to be package ID
bits.

Current code gets package ID by shifting out all the APIC-ID bits that
Linux supports, rather than shifting out all the APIC-ID bits that
CPUID.1F enumerates. This introduces problems when CPUID.1F enumerates a
level that Linux does not support.

For example, on a single package AlderLake-N, there are 2 Ecore Modules
with 4 atom cores in each module.  Linux does not support the Module
level and interprets the Module ID bits as package ID and erroneously
reports a multi module system as a multi-package system.

Fix this by using APIC-ID bits above all the CPUID.1F enumerated levels
as package ID.

[ dhansen: spelling fix ]

Fixes: 7745f03eb3 ("x86/topology: Add CPUID.1F multi-die/package support")
Suggested-by: Len Brown <len.brown@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Len Brown <len.brown@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20221014090147.1836-4-rui.zhang@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:15 +01:00
Yazen Ghannam
f5ad52da14 x86/topology: Set cpu_die_id only if DIE_TYPE found
[ Upstream commit cb09a379724d299c603a7a79f444f52a9a75b8d2 ]

CPUID Leaf 0x1F defines a DIE_TYPE level (nb: ECX[8:15] level type == 0x5),
but CPUID Leaf 0xB does not. However, detect_extended_topology() will
set struct cpuinfo_x86.cpu_die_id regardless of whether a valid Die ID
was found.

Only set cpu_die_id if a DIE_TYPE level is found. CPU topology code may
use another value for cpu_die_id, e.g. the AMD NodeId on AMD-based
systems. Code ordering should be maintained so that the CPUID Leaf 0x1F
Die ID value will take precedence on systems that may use another value.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201109210659.754018-5-Yazen.Ghannam@amd.com
Stable-dep-of: 2b12a7a126d6 ("x86/topology: Fix multiple packages shown on a single-package system")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:15 +01:00
Sean Christopherson
570fa3bcd2 KVM: x86: Treat #DBs from the emulator as fault-like (code and DR7.GD=1)
[ Upstream commit 5623f751bd9c438ed12840e086f33c4646440d19 ]

Add a dedicated "exception type" for #DBs, as #DBs can be fault-like or
trap-like depending the sub-type of #DB, and effectively defer the
decision of what to do with the #DB to the caller.

For the emulator's two calls to exception_type(), treat the #DB as
fault-like, as the emulator handles only code breakpoint and general
detect #DBs, both of which are fault-like.

For event injection, which uses exception_type() to determine whether to
set EFLAGS.RF=1 on the stack, keep the current behavior of not setting
RF=1 for #DBs.  Intel and AMD explicitly state RF isn't set on code #DBs,
so exempting by failing the "== EXCPT_FAULT" check is correct.  The only
other fault-like #DB is General Detect, and despite Intel and AMD both
strongly implying (through omission) that General Detect #DBs should set
RF=1, hardware (multiple generations of both Intel and AMD), in fact does
not.  Through insider knowledge, extreme foresight, sheer dumb luck, or
some combination thereof, KVM correctly handled RF for General Detect #DBs.

Fixes: 38827dbd3f ("KVM: x86: Do not update EFLAGS on faulting emulation")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20220830231614.3580124-9-seanjc@google.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:15 +01:00
Sean Christopherson
e5d7c6786b KVM: x86: Trace re-injected exceptions
[ Upstream commit a61d7c5432ac5a953bbcec17af031661c2bd201d ]

Trace exceptions that are re-injected, not just those that KVM is
injecting for the first time.  Debugging re-injection bugs is painful
enough as is, not having visibility into what KVM is doing only makes
things worse.

Delay propagating pending=>injected in the non-reinjection path so that
the tracing can properly identify reinjected exceptions.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <25470690a38b4d2b32b6204875dd35676c65c9f2.1651440202.git.maciej.szmigiero@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: 5623f751bd9c ("KVM: x86: Treat #DBs from the emulator as fault-like (code and DR7.GD=1)")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:15 +01:00
Sean Christopherson
8364786152 KVM: nVMX: Don't propagate vmcs12's PERF_GLOBAL_CTRL settings to vmcs02
[ Upstream commit def9d705c05eab3fdedeb10ad67907513b12038e ]

Don't propagate vmcs12's VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL to vmcs02.
KVM doesn't disallow L1 from using VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL
even when KVM itself doesn't use the control, e.g. due to the various
CPU errata that where the MSR can be corrupted on VM-Exit.

Preserve KVM's (vmcs01) setting to hopefully avoid having to toggle the
bit in vmcs02 at a later point.  E.g. if KVM is loading PERF_GLOBAL_CTRL
when running L1, then odds are good KVM will also load the MSR when
running L2.

Fixes: 8bf00a5299 ("KVM: VMX: add support for switching of PERF_GLOBAL_CTRL")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20220830133737.1539624-18-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:14 +01:00
Sean Christopherson
523e1dd9f8 KVM: nVMX: Pull KVM L0's desired controls directly from vmcs01
[ Upstream commit 389ab25216c9d09e0d335e764eeeb84c2089614f ]

When preparing controls for vmcs02, grab KVM's desired controls from
vmcs01's shadow state instead of recalculating the controls from scratch,
or in the secondary execution controls, instead of using the dedicated
cache.  Calculating secondary exec controls is eye-poppingly expensive
due to the guest CPUID checks, hence the dedicated cache, but the other
calculations aren't exactly free either.

Explicitly clear several bits (x2APIC, DESC exiting, and load EFER on
exit) as appropriate as they may be set in vmcs01, whereas the previous
implementation relied on dynamic bits being cleared in the calculator.

Intentionally propagate VM_{ENTRY,EXIT}_LOAD_IA32_PERF_GLOBAL_CTRL from
vmcs01 to vmcs02.  Whether or not PERF_GLOBAL_CTRL is loaded depends on
whether or not perf itself is active, so unless perf stops between the
exit from L1 and entry to L2, vmcs01 will hold the desired value.  This
is purely an optimization as atomic_switch_perf_msrs() will set/clear
the control as needed at VM-Enter, i.e. it avoids two extra VMWRITEs in
the case where perf is active (versus starting with the bits clear in
vmcs02, which was the previous behavior).

Cc: Zeng Guang <guang.zeng@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210810171952.2758100-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: def9d705c05e ("KVM: nVMX: Don't propagate vmcs12's PERF_GLOBAL_CTRL settings to vmcs02")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:14 +01:00
Chen Zhongjin
b55d6ea965 x86/unwind/orc: Fix unreliable stack dump with gcov
[ Upstream commit 230db82413c091bc16acee72650f48d419cebe49 ]

When a console stack dump is initiated with CONFIG_GCOV_PROFILE_ALL
enabled, show_trace_log_lvl() gets out of sync with the ORC unwinder,
causing the stack trace to show all text addresses as unreliable:

  # echo l > /proc/sysrq-trigger
  [  477.521031] sysrq: Show backtrace of all active CPUs
  [  477.523813] NMI backtrace for cpu 0
  [  477.524492] CPU: 0 PID: 1021 Comm: bash Not tainted 6.0.0 #65
  [  477.525295] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-1.fc36 04/01/2014
  [  477.526439] Call Trace:
  [  477.526854]  <TASK>
  [  477.527216]  ? dump_stack_lvl+0xc7/0x114
  [  477.527801]  ? dump_stack+0x13/0x1f
  [  477.528331]  ? nmi_cpu_backtrace.cold+0xb5/0x10d
  [  477.528998]  ? lapic_can_unplug_cpu+0xa0/0xa0
  [  477.529641]  ? nmi_trigger_cpumask_backtrace+0x16a/0x1f0
  [  477.530393]  ? arch_trigger_cpumask_backtrace+0x1d/0x30
  [  477.531136]  ? sysrq_handle_showallcpus+0x1b/0x30
  [  477.531818]  ? __handle_sysrq.cold+0x4e/0x1ae
  [  477.532451]  ? write_sysrq_trigger+0x63/0x80
  [  477.533080]  ? proc_reg_write+0x92/0x110
  [  477.533663]  ? vfs_write+0x174/0x530
  [  477.534265]  ? handle_mm_fault+0x16f/0x500
  [  477.534940]  ? ksys_write+0x7b/0x170
  [  477.535543]  ? __x64_sys_write+0x1d/0x30
  [  477.536191]  ? do_syscall_64+0x6b/0x100
  [  477.536809]  ? entry_SYSCALL_64_after_hwframe+0x63/0xcd
  [  477.537609]  </TASK>

This happens when the compiled code for show_stack() has a single word
on the stack, and doesn't use a tail call to show_stack_log_lvl().
(CONFIG_GCOV_PROFILE_ALL=y is the only known case of this.)  Then the
__unwind_start() skip logic hits an off-by-one bug and fails to unwind
all the way to the intended starting frame.

Fix it by reverting the following commit:

  f1d9a2abff ("x86/unwind/orc: Don't skip the first frame for inactive tasks")

The original justification for that commit no longer exists.  That
original issue was later fixed in a different way, with the following
commit:

  f2ac57a4c4 ("x86/unwind/orc: Fix inactive tasks with stack pointer in %sp on GCC 10 compiled kernels")

Fixes: f1d9a2abff ("x86/unwind/orc: Don't skip the first frame for inactive tasks")
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
[jpoimboe: rewrite commit log]
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-03 23:57:51 +09:00
Maxim Levitsky
fb94152aae perf/x86/intel/lbr: Use setup_clear_cpu_cap() instead of clear_cpu_cap()
[ Upstream commit b329f5ddc9ce4b622d9c7aaf5c6df4de52caf91a ]

clear_cpu_cap(&boot_cpu_data) is very similar to setup_clear_cpu_cap()
except that the latter also sets a bit in 'cpu_caps_cleared' which
later clears the same cap in secondary cpus, which is likely what is
meant here.

Fixes: 47125db27e ("perf/x86/intel/lbr: Support Architectural LBR")
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lkml.kernel.org/r/20220718141123.136106-2-mlevitsk@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-03 23:57:51 +09:00
Nathan Chancellor
6ab2287b26 x86/Kconfig: Drop check for -mabi=ms for CONFIG_EFI_STUB
commit 33806e7cb8d50379f55c3e8f335e91e1b359dc7b upstream.

A recent change in LLVM made CONFIG_EFI_STUB unselectable because it no
longer pretends to support -mabi=ms, breaking the dependency in
Kconfig. Lack of CONFIG_EFI_STUB can prevent kernels from booting via
EFI in certain circumstances.

This check was added by

  8f24f8c2fc ("efi/libstub: Annotate firmware routines as __efiapi")

to ensure that __attribute__((ms_abi)) was available, as -mabi=ms is
not actually used in any cflags.

According to the GCC documentation, this attribute has been supported
since GCC 4.4.7. The kernel currently requires GCC 5.1 so this check is
not necessary; even when that change landed in 5.6, the kernel required
GCC 4.9 so it was unnecessary then as well.

Clang supports __attribute__((ms_abi)) for all versions that are
supported for building the kernel so no additional check is needed.
Remove the 'depends on' line altogether to allow CONFIG_EFI_STUB to be
selected when CONFIG_EFI is enabled, regardless of compiler.

Fixes: 8f24f8c2fc ("efi/libstub: Annotate firmware routines as __efiapi")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Cc: stable@vger.kernel.org
Link: d1ad006a8f
[nathan: Fix conflict due to lack of c6dbd3e5e69c in older trees]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-30 09:41:19 +01:00
Adrian Hunter
da54c5f4b5 perf/x86/intel/pt: Relax address filter validation
commit c243cecb58e3905baeace8827201c14df8481e2a upstream.

The requirement for 64-bit address filters is that they are canonical
addresses. In other respects any address range is allowed which would
include user space addresses.

That can be useful for tracing virtual machine guests because address
filtering can be used to advantage in place of current privilege level
(CPL) filtering.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220131072453.2839535-2-adrian.hunter@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-30 09:41:19 +01:00
Charlotte Tan
ef11e8ec00 iommu/vt-d: Allow NVS regions in arch_rmrr_sanity_check()
[ Upstream commit 5566e68d829f5d87670d5984c1c2ccb4c518405f ]

arch_rmrr_sanity_check() warns if the RMRR is not covered by an ACPI
Reserved region, but it seems like it should accept an NVS region as
well. The ACPI spec
https://uefi.org/specs/ACPI/6.5/15_System_Address_Map_Interfaces.html
uses similar wording for "Reserved" and "NVS" region types; for NVS
regions it says "This range of addresses is in use or reserved by the
system and must not be used by the operating system."

There is an old comment on this mailing list that also suggests NVS
regions should pass the arch_rmrr_sanity_check() test:

 The warnings come from arch_rmrr_sanity_check() since it checks whether
 the region is E820_TYPE_RESERVED. However, if the purpose of the check
 is to detect RMRR has regions that may be used by OS as free memory,
 isn't  E820_TYPE_NVS safe, too?

This patch overlaps with another proposed patch that would add the region
type to the log since sometimes the bug reporter sees this log on the
console but doesn't know to include the kernel log:

https://lore.kernel.org/lkml/20220611204859.234975-3-atomlin@redhat.com/

Here's an example of the "Firmware Bug" apparent false positive (wrapped
for line length):

 DMAR: [Firmware Bug]: No firmware reserved region can cover this RMRR
       [0x000000006f760000-0x000000006f762fff], contact BIOS vendor for
       fixes
 DMAR: [Firmware Bug]: Your BIOS is broken; bad RMRR
       [0x000000006f760000-0x000000006f762fff]

This is the snippet from the e820 table:

 BIOS-e820: [mem 0x0000000068bff000-0x000000006ebfefff] reserved
 BIOS-e820: [mem 0x000000006ebff000-0x000000006f9fefff] ACPI NVS
 BIOS-e820: [mem 0x000000006f9ff000-0x000000006fffefff] ACPI data

Fixes: f036c7fa0a ("iommu/vt-d: Check VT-d RMRR region in BIOS is reported as reserved")
Cc: Will Mortensen <will@extrahop.com>
Link: https://lore.kernel.org/linux-iommu/64a5843d-850d-e58c-4fc2-0a0eeeb656dc@nec.com/
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216443
Signed-off-by: Charlotte Tan <charlotte@extrahop.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Link: https://lore.kernel.org/r/20220929044449.32515-1-charlotte@extrahop.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-30 09:41:17 +01:00
Borislav Petkov
0fb04676c4 x86/microcode/AMD: Apply the patch early on every logical thread
commit e7ad18d1169c62e6c78c01ff693fd362d9d65278 upstream.

Currently, the patch application logic checks whether the revision
needs to be applied on each logical CPU (SMT thread). Therefore, on SMT
designs where the microcode engine is shared between the two threads,
the application happens only on one of them as that is enough to update
the shared microcode engine.

However, there are microcode patches which do per-thread modification,
see Link tag below.

Therefore, drop the revision check and try applying on each thread. This
is what the BIOS does too so this method is very much tested.

Btw, change only the early paths. On the late loading paths, there's no
point in doing per-thread modification because if is it some case like
in the bugzilla below - removing a CPUID flag - the kernel cannot go and
un-use features it has detected are there early. For that, one should
use early loading anyway.

  [ bp: Fixes does not contain the oldest commit which did check for
    equality but that is good enough. ]

Fixes: 8801b3fcb5 ("x86/microcode/AMD: Rework container parsing")
Reported-by:  Ștefan Talpalaru <stefantalpalaru@yahoo.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by:  Ștefan Talpalaru <stefantalpalaru@yahoo.com>
Cc: <stable@vger.kernel.org>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216211
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-30 09:41:15 +01:00
Kees Cook
1f730d4ae6 x86/entry: Work around Clang __bdos() bug
[ Upstream commit 3e1730842f142add55dc658929221521a9ea62b6 ]

Clang produces a false positive when building with CONFIG_FORTIFY_SOURCE=y
and CONFIG_UBSAN_BOUNDS=y when operating on an array with a dynamic
offset. Work around this by using a direct assignment of an empty
instance. Avoids this warning:

../include/linux/fortify-string.h:309:4: warning: call to __write_overflow_field declared with 'warn
ing' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wat
tribute-warning]
                        __write_overflow_field(p_size_field, size);
                        ^

which was isolated to the memset() call in xen_load_idt().

Note that this looks very much like another bug that was worked around:
https://github.com/ClangBuiltLinux/linux/issues/1592

Cc: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: xen-devel@lists.xenproject.org
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/lkml/41527d69-e8ab-3f86-ff37-6b298c01d5bc@oracle.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:45 +02:00
Vitaly Kuznetsov
7ae8bed908 x86/hyperv: Fix 'struct hv_enlightened_vmcs' definition
[ Upstream commit ea9da788a61e47e7ab9cbad397453e51cd82ac0d ]

Section 1.9 of TLFS v6.0b says:

"All structures are padded in such a way that fields are aligned
naturally (that is, an 8-byte field is aligned to an offset of 8 bytes
and so on)".

'struct enlightened_vmcs' has a glitch:

...
        struct {
                u32                nested_flush_hypercall:1; /*   836: 0  4 */
                u32                msr_bitmap:1;         /*   836: 1  4 */
                u32                reserved:30;          /*   836: 2  4 */
        } hv_enlightenments_control;                     /*   836     4 */
        u32                        hv_vp_id;             /*   840     4 */
        u64                        hv_vm_id;             /*   844     8 */
        u64                        partition_assist_page; /*   852     8 */
...

And the observed values in 'partition_assist_page' make no sense at
all. Fix the layout by padding the structure properly.

Fixes: 68d1eb72ee ("x86/hyper-v: define struct hv_enlightened_vmcs and clean field bits")
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220830133737.1539624-2-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:40 +02:00
Luciano Leão
1ef5798638 x86/cpu: Include the header of init_ia32_feat_ctl()'s prototype
[ Upstream commit 30ea703a38ef76ca119673cd8bdd05c6e068e2ac ]

Include the header containing the prototype of init_ia32_feat_ctl(),
solving the following warning:

  $ make W=1 arch/x86/kernel/cpu/feat_ctl.o
  arch/x86/kernel/cpu/feat_ctl.c:112:6: warning: no previous prototype for ‘init_ia32_feat_ctl’ [-Wmissing-prototypes]
    112 | void init_ia32_feat_ctl(struct cpuinfo_x86 *c)

This warning appeared after commit

  5d5103595e ("x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup")

had moved the function init_ia32_feat_ctl()'s prototype from
arch/x86/kernel/cpu/cpu.h to arch/x86/include/asm/cpu.h.

Note that, before the commit mentioned above, the header include "cpu.h"
(arch/x86/kernel/cpu/cpu.h) was added by commit

  0e79ad863d ("x86/cpu: Fix a -Wmissing-prototypes warning for init_ia32_feat_ctl()")

solely to fix init_ia32_feat_ctl()'s missing prototype. So, the header
include "cpu.h" is no longer necessary.

  [ bp: Massage commit message. ]

Fixes: 5d5103595e ("x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup")
Signed-off-by: Luciano Leão <lucianorsleao@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nícolas F. R. A. Prado <n@nfraprado.net>
Link: https://lore.kernel.org/r/20220922200053.1357470-1-lucianorsleao@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:21 +02:00
Kees Cook
6ed7b05a35 x86/microcode/AMD: Track patch allocation size explicitly
[ Upstream commit 712f210a457d9c32414df246a72781550bc23ef6 ]

In preparation for reducing the use of ksize(), record the actual
allocation size for later memcpy(). This avoids copying extra
(uninitialized!) bytes into the patch buffer when the requested
allocation size isn't exactly the size of a kmalloc bucket.
Additionally, fix potential future issues where runtime bounds checking
will notice that the buffer was allocated to a smaller value than
returned by ksize().

Fixes: 757885e94a ("x86, microcode, amd: Early microcode patch loading support for AMD")
Suggested-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/lkml/CA+DvKQ+bp7Y7gmaVhacjv9uF6Ar-o4tet872h4Q8RPYPJjcJQA@mail.gmail.com/
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:21 +02:00