33864 Commits

Author SHA1 Message Date
Tony W Wang-oc
0f378d73d4 x86/apic: Mask IOAPIC entries when disabling the local APIC
When a system suspends, the local APIC is disabled in the suspend sequence,
but the IOAPIC is left in the current state. This means unmasked interrupt
lines stay unmasked. This is usually the case for IOAPIC pin 9 to which the
ACPI interrupt is connected.

That means that in suspended state the IOAPIC can respond to an external
interrupt, e.g. the wakeup via keyboard/RTC/ACPI, but the interrupt message
cannot be handled by the disabled local APIC. As a consequence the Remote
IRR bit is set, but the local APIC does not send an EOI to acknowledge
it. This causes the affected interrupt line to become stale and the stale
Remote IRR bit will cause a hang when __synchronize_hardirq() is invoked
for that interrupt line.

To prevent this, mask all IOAPIC entries before disabling the local
APIC. The resume code already has the unmask operation inside.

[ tglx: Massaged changelog ]

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/1579076539-7267-1-git-send-email-TonyWWang-oc@zhaoxin.com
2020-02-07 15:32:16 +01:00
Dexuan Cui
05bd330a7f x86/hyperv: Suspend/resume the hypercall page for hibernation
For hibernation the hypercall page must be disabled before the hibernation
image is created so that subsequent hypercall operations fail safely. On
resume the hypercall page has to be restored and reenabled to ensure proper
operation of the resumed kernel.

Implement the necessary suspend/resume callbacks.

[ tglx: Decrypted changelog ]

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1578350559-130275-1-git-send-email-decui@microsoft.com
2020-02-01 09:41:16 +01:00
Thomas Gleixner
6f1a4891a5 x86/apic/msi: Plug non-maskable MSI affinity race
Evan tracked down a subtle race between the update of the MSI message and
the device raising an interrupt internally on PCI devices which do not
support MSI masking. The update of the MSI message is non-atomic and
consists of either 2 or 3 sequential 32bit wide writes to the PCI config
space.

   - Write address low 32bits
   - Write address high 32bits (If supported by device)
   - Write data

When an interrupt is migrated then both address and data might change, so
the kernel attempts to mask the MSI interrupt first. But for MSI masking is
optional, so there exist devices which do not provide it. That means that
if the device raises an interrupt internally between the writes then a MSI
message is sent built from half updated state.

On x86 this can lead to spurious interrupts on the wrong interrupt
vector when the affinity setting changes both address and data. As a
consequence the device interrupt can be lost causing the device to
become stuck or malfunctioning.

Evan tried to handle that by disabling MSI accross an MSI message
update. That's not feasible because disabling MSI has issues on its own:

 If MSI is disabled the PCI device is routing an interrupt to the legacy
 INTx mechanism. The INTx delivery can be disabled, but the disablement is
 not working on all devices.

 Some devices lose interrupts when both MSI and INTx delivery are disabled.

Another way to solve this would be to enforce the allocation of the same
vector on all CPUs in the system for this kind of screwed devices. That
could be done, but it would bring back the vector space exhaustion problems
which got solved a few years ago.

Fortunately the high address (if supported by the device) is only relevant
when X2APIC is enabled which implies interrupt remapping. In the interrupt
remapping case the affinity setting is happening at the interrupt remapping
unit and the PCI MSI message is programmed only once when the PCI device is
initialized.

That makes it possible to solve it with a two step update:

  1) Target the MSI msg to the new vector on the current target CPU

  2) Target the MSI msg to the new vector on the new target CPU

In both cases writing the MSI message is only changing a single 32bit word
which prevents the issue of inconsistency.

After writing the final destination it is necessary to check whether the
device issued an interrupt while the intermediate state #1 (new vector,
current CPU) was in effect.

This is possible because the affinity change is always happening on the
current target CPU. The code runs with interrupts disabled, so the
interrupt can be detected by checking the IRR of the local APIC. If the
vector is pending in the IRR then the interrupt is retriggered on the new
target CPU by sending an IPI for the associated vector on the target CPU.

This can cause spurious interrupts on both the local and the new target
CPU.

 1) If the new vector is not in use on the local CPU and the device
    affected by the affinity change raised an interrupt during the
    transitional state (step #1 above) then interrupt entry code will
    ignore that spurious interrupt. The vector is marked so that the
    'No irq handler for vector' warning is supressed once.

 2) If the new vector is in use already on the local CPU then the IRR check
    might see an pending interrupt from the device which is using this
    vector. The IPI to the new target CPU will then invoke the handler of
    the device, which got the affinity change, even if that device did not
    issue an interrupt

 3) If the new vector is in use already on the local CPU and the device
    affected by the affinity change raised an interrupt during the
    transitional state (step #1 above) then the handler of the device which
    uses that vector on the local CPU will be invoked.

expose issues in device driver interrupt handlers which are not prepared to
handle a spurious interrupt correctly. This not a regression, it's just
exposing something which was already broken as spurious interrupts can
happen for a lot of reasons and all driver handlers need to be able to deal
with them.

Reported-by: Evan Green <evgreen@chromium.org>
Debugged-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Evan Green <evgreen@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87imkr4s7n.fsf@nanos.tec.linutronix.de
2020-02-01 09:31:47 +01:00
Steven Clarkson
2b73ea3796 x86/boot: Handle malformed SRAT tables during early ACPI parsing
Break an infinite loop when early parsing of the SRAT table is caused
by a subtable with zero length. Known to affect the ASUS WS X299 SAGE
motherboard with firmware version 1201 which has a large block of
zeros in its SRAT table. The kernel could boot successfully on this
board/firmware prior to the introduction of early parsing this table or
after a BIOS update.

 [ bp: Fixup whitespace damage and commit message. Make it return 0 to
   denote that there are no immovable regions because who knows what
   else is broken in this BIOS. ]

Fixes: 02a3e3cdb7f1 ("x86/boot: Parse SRAT table and count immovable memory regions")
Signed-off-by: Steven Clarkson <sc@lambdal.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: linux-acpi@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206343
Link: https://lkml.kernel.org/r/CAHKq8taGzj0u1E_i=poHUam60Bko5BpiJ9jn0fAupFUYexvdUQ@mail.gmail.com
2020-01-31 20:03:23 +01:00
Thomas Gleixner
979923871f x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode
Tony reported a boot regression caused by the recent workaround for systems
which have a disabled (clock gate off) PIT.

On his machine the kernel fails to initialize the PIT because
apic_needs_pit() does not take into account whether the local APIC
interrupt delivery mode will actually allow to setup and use the local
APIC timer. This should be easy to reproduce with acpi=off on the
command line which also disables HPET.

Due to the way the PIT/HPET and APIC setup ordering works (APIC setup can
require working PIT/HPET) the information is not available at the point
where apic_needs_pit() makes this decision.

To address this, split out the interrupt mode selection from
apic_intr_mode_init(), invoke the selection before making the decision
whether PIT is required or not, and add the missing checks into
apic_needs_pit().

Fixes: c8c4076723da ("x86/timer: Skip PIT initialization on modern chipsets")
Reported-by: Anthony Buckley <tony.buckley000@gmail.com>
Tested-by: Anthony Buckley <tony.buckley000@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Daniel Drake <drake@endlessm.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206125
Link: https://lore.kernel.org/r/87sgk6tmk2.fsf@nanos.tec.linutronix.de
2020-01-29 12:50:12 +01:00
Ingo Molnar
6bd3357b61 Merge branches 'x86/hyperv', 'x86/kdump' and 'x86/misc' into x86/urgent, to pick up single-commit branches
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-28 19:08:52 +01:00
Masami Hiramatsu
8b7e20a7ba x86/decoder: Add TEST opcode to Group3-2
Add TEST opcode to Group3-2 reg=001b as same as Group3-1 does.

Commit

  12a78d43de76 ("x86/decoder: Add new TEST instruction pattern")

added a TEST opcode assignment to f6 XX/001/XXX (Group 3-1), but did
not add f7 XX/001/XXX (Group 3-2).

Actually, this TEST opcode variant (ModRM.reg /1) is not described in
the Intel SDM Vol2 but in AMD64 Architecture Programmer's Manual Vol.3,
Appendix A.2 Table A-6. ModRM.reg Extensions for the Primary Opcode Map.

Without this fix, Randy found a warning by insn_decoder_test related
to this issue as below.

    HOSTCC  arch/x86/tools/insn_decoder_test
    HOSTCC  arch/x86/tools/insn_sanity
    TEST    posttest
  arch/x86/tools/insn_decoder_test: warning: Found an x86 instruction decoder bug, please report this.
  arch/x86/tools/insn_decoder_test: warning: ffffffff81000bf1:	f7 0b 00 01 08 00    	testl  $0x80100,(%rbx)
  arch/x86/tools/insn_decoder_test: warning: objdump says 6 bytes, but insn_get_length() says 2
  arch/x86/tools/insn_decoder_test: warning: Decoded and checked 11913894 instructions with 1 failures
    TEST    posttest
  arch/x86/tools/insn_sanity: Success: decoded and checked 1000000 random instructions with 0 errors (seed:0x871ce29c)

To fix this error, add the TEST opcode according to AMD64 APM Vol.3.

 [ bp: Massage commit message. ]

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lkml.kernel.org/r/157966631413.9580.10311036595431878351.stgit@devnote2
2020-01-22 12:17:32 +01:00
Xiaochen Shen
32ada3b9e0 x86/resctrl: Clean up unused function parameter in mkdir path
Commit

  334b0f4e9b1b ("x86/resctrl: Fix a deadlock due to inaccurate reference")

changed the argument to rdtgroup_kn_lock_live()/rdtgroup_kn_unlock()
within mkdir_rdt_prepare(). That change resulted in an unused function
parameter to mkdir_rdt_prepare().

Clean up the unused function parameter in mkdir_rdt_prepare() and its
callers rdtgroup_mkdir_mon() and rdtgroup_mkdir_ctrl_mon().

Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1578500886-21771-5-git-send-email-xiaochen.shen@intel.com
2020-01-20 17:00:41 +01:00
Xiaochen Shen
334b0f4e9b x86/resctrl: Fix a deadlock due to inaccurate reference
There is a race condition which results in a deadlock when rmdir and
mkdir execute concurrently:

$ ls /sys/fs/resctrl/c1/mon_groups/m1/
cpus  cpus_list  mon_data  tasks

Thread 1: rmdir /sys/fs/resctrl/c1
Thread 2: mkdir /sys/fs/resctrl/c1/mon_groups/m1

3 locks held by mkdir/48649:
 #0:  (sb_writers#17){.+.+}, at: [<ffffffffb4ca2aa0>] mnt_want_write+0x20/0x50
 #1:  (&type->i_mutex_dir_key#8/1){+.+.}, at: [<ffffffffb4c8c13b>] filename_create+0x7b/0x170
 #2:  (rdtgroup_mutex){+.+.}, at: [<ffffffffb4a4389d>] rdtgroup_kn_lock_live+0x3d/0x70

4 locks held by rmdir/48652:
 #0:  (sb_writers#17){.+.+}, at: [<ffffffffb4ca2aa0>] mnt_want_write+0x20/0x50
 #1:  (&type->i_mutex_dir_key#8/1){+.+.}, at: [<ffffffffb4c8c3cf>] do_rmdir+0x13f/0x1e0
 #2:  (&type->i_mutex_dir_key#8){++++}, at: [<ffffffffb4c86d5d>] vfs_rmdir+0x4d/0x120
 #3:  (rdtgroup_mutex){+.+.}, at: [<ffffffffb4a4389d>] rdtgroup_kn_lock_live+0x3d/0x70

Thread 1 is deleting control group "c1". Holding rdtgroup_mutex,
kernfs_remove() removes all kernfs nodes under directory "c1"
recursively, then waits for sub kernfs node "mon_groups" to drop active
reference.

Thread 2 is trying to create a subdirectory "m1" in the "mon_groups"
directory. The wrapper kernfs_iop_mkdir() takes an active reference to
the "mon_groups" directory but the code drops the active reference to
the parent directory "c1" instead.

As a result, Thread 1 is blocked on waiting for active reference to drop
and never release rdtgroup_mutex, while Thread 2 is also blocked on
trying to get rdtgroup_mutex.

Thread 1 (rdtgroup_rmdir)   Thread 2 (rdtgroup_mkdir)
(rmdir /sys/fs/resctrl/c1)  (mkdir /sys/fs/resctrl/c1/mon_groups/m1)
-------------------------   -------------------------
                            kernfs_iop_mkdir
                              /*
                               * kn: "m1", parent_kn: "mon_groups",
                               * prgrp_kn: parent_kn->parent: "c1",
                               *
                               * "mon_groups", parent_kn->active++: 1
                               */
                              kernfs_get_active(parent_kn)
kernfs_iop_rmdir
  /* "c1", kn->active++ */
  kernfs_get_active(kn)

  rdtgroup_kn_lock_live
    atomic_inc(&rdtgrp->waitcount)
    /* "c1", kn->active-- */
    kernfs_break_active_protection(kn)
    mutex_lock

  rdtgroup_rmdir_ctrl
    free_all_child_rdtgrp
      sentry->flags = RDT_DELETED

    rdtgroup_ctrl_remove
      rdtgrp->flags = RDT_DELETED
      kernfs_get(kn)
      kernfs_remove(rdtgrp->kn)
        __kernfs_remove
          /* "mon_groups", sub_kn */
          atomic_add(KN_DEACTIVATED_BIAS, &sub_kn->active)
          kernfs_drain(sub_kn)
            /*
             * sub_kn->active == KN_DEACTIVATED_BIAS + 1,
             * waiting on sub_kn->active to drop, but it
             * never drops in Thread 2 which is blocked
             * on getting rdtgroup_mutex.
             */
Thread 1 hangs here ---->
            wait_event(sub_kn->active == KN_DEACTIVATED_BIAS)
            ...
                              rdtgroup_mkdir
                                rdtgroup_mkdir_mon(parent_kn, prgrp_kn)
                                  mkdir_rdt_prepare(parent_kn, prgrp_kn)
                                    rdtgroup_kn_lock_live(prgrp_kn)
                                      atomic_inc(&rdtgrp->waitcount)
                                      /*
                                       * "c1", prgrp_kn->active--
                                       *
                                       * The active reference on "c1" is
                                       * dropped, but not matching the
                                       * actual active reference taken
                                       * on "mon_groups", thus causing
                                       * Thread 1 to wait forever while
                                       * holding rdtgroup_mutex.
                                       */
                                      kernfs_break_active_protection(
                                                               prgrp_kn)
                                      /*
                                       * Trying to get rdtgroup_mutex
                                       * which is held by Thread 1.
                                       */
Thread 2 hangs here ---->             mutex_lock
                                      ...

The problem is that the creation of a subdirectory in the "mon_groups"
directory incorrectly releases the active protection of its parent
directory instead of itself before it starts waiting for rdtgroup_mutex.
This is triggered by the rdtgroup_mkdir() flow calling
rdtgroup_kn_lock_live()/rdtgroup_kn_unlock() with kernfs node of the
parent control group ("c1") as argument. It should be called with kernfs
node "mon_groups" instead. What is currently missing is that the
kn->priv of "mon_groups" is NULL instead of pointing to the rdtgrp.

Fix it by pointing kn->priv to rdtgrp when "mon_groups" is created. Then
it could be passed to rdtgroup_kn_lock_live()/rdtgroup_kn_unlock()
instead. And then it operates on the same rdtgroup structure but handles
the active reference of kernfs node "mon_groups" to prevent deadlock.
The same changes are also made to the "mon_data" directories.

This results in some unused function parameters that will be cleaned up
in follow-up patch as the focus here is on the fix only in support of
backporting efforts.

Fixes: c7d9aac61311 ("x86/intel_rdt/cqm: Add mkdir support for RDT monitoring")
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1578500886-21771-4-git-send-email-xiaochen.shen@intel.com
2020-01-20 16:57:53 +01:00
Xiaochen Shen
074fadee59 x86/resctrl: Fix use-after-free due to inaccurate refcount of rdtgroup
There is a race condition in the following scenario which results in an
use-after-free issue when reading a monitoring file and deleting the
parent ctrl_mon group concurrently:

Thread 1 calls atomic_inc() to take refcount of rdtgrp and then calls
kernfs_break_active_protection() to drop the active reference of kernfs
node in rdtgroup_kn_lock_live().

In Thread 2, kernfs_remove() is a blocking routine. It waits on all sub
kernfs nodes to drop the active reference when removing all subtree
kernfs nodes recursively. Thread 2 could block on kernfs_remove() until
Thread 1 calls kernfs_break_active_protection(). Only after
kernfs_remove() completes the refcount of rdtgrp could be trusted.

Before Thread 1 calls atomic_inc() and kernfs_break_active_protection(),
Thread 2 could call kfree() when the refcount of rdtgrp (sentry) is 0
instead of 1 due to the race.

In Thread 1, in rdtgroup_kn_unlock(), referring to earlier rdtgrp memory
(rdtgrp->waitcount) which was already freed in Thread 2 results in
use-after-free issue.

Thread 1 (rdtgroup_mondata_show)  Thread 2 (rdtgroup_rmdir)
--------------------------------  -------------------------
rdtgroup_kn_lock_live
  /*
   * kn active protection until
   * kernfs_break_active_protection(kn)
   */
  rdtgrp = kernfs_to_rdtgroup(kn)
                                  rdtgroup_kn_lock_live
                                    atomic_inc(&rdtgrp->waitcount)
                                    mutex_lock
                                  rdtgroup_rmdir_ctrl
                                    free_all_child_rdtgrp
                                      /*
                                       * sentry->waitcount should be 1
                                       * but is 0 now due to the race.
                                       */
                                      kfree(sentry)*[1]
  /*
   * Only after kernfs_remove()
   * completes, the refcount of
   * rdtgrp could be trusted.
   */
  atomic_inc(&rdtgrp->waitcount)
  /* kn->active-- */
  kernfs_break_active_protection(kn)
                                    rdtgroup_ctrl_remove
                                      rdtgrp->flags = RDT_DELETED
                                      /*
                                       * Blocking routine, wait for
                                       * all sub kernfs nodes to drop
                                       * active reference in
                                       * kernfs_break_active_protection.
                                       */
                                      kernfs_remove(rdtgrp->kn)
                                  rdtgroup_kn_unlock
                                    mutex_unlock
                                    atomic_dec_and_test(
                                                &rdtgrp->waitcount)
                                    && (flags & RDT_DELETED)
                                      kernfs_unbreak_active_protection(kn)
                                      kfree(rdtgrp)
  mutex_lock
mon_event_read
rdtgroup_kn_unlock
  mutex_unlock
  /*
   * Use-after-free: refer to earlier rdtgrp
   * memory which was freed in [1].
   */
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
    /* kn->active++ */
    kernfs_unbreak_active_protection(kn)
    kfree(rdtgrp)

Fix it by moving free_all_child_rdtgrp() to after kernfs_remove() in
rdtgroup_rmdir_ctrl() to ensure it has the accurate refcount of rdtgrp.

Fixes: f3cbeacaa06e ("x86/intel_rdt/cqm: Add rmdir support")
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1578500886-21771-3-git-send-email-xiaochen.shen@intel.com
2020-01-20 16:56:11 +01:00
Xiaochen Shen
b8511ccc75 x86/resctrl: Fix use-after-free when deleting resource groups
A resource group (rdtgrp) contains a reference count (rdtgrp->waitcount)
that indicates how many waiters expect this rdtgrp to exist. Waiters
could be waiting on rdtgroup_mutex or some work sitting on a task's
workqueue for when the task returns from kernel mode or exits.

The deletion of a rdtgrp is intended to have two phases:

  (1) while holding rdtgroup_mutex the necessary cleanup is done and
  rdtgrp->flags is set to RDT_DELETED,

  (2) after releasing the rdtgroup_mutex, the rdtgrp structure is freed
  only if there are no waiters and its flag is set to RDT_DELETED. Upon
  gaining access to rdtgroup_mutex or rdtgrp, a waiter is required to check
  for the RDT_DELETED flag.

When unmounting the resctrl file system or deleting ctrl_mon groups,
all of the subdirectories are removed and the data structure of rdtgrp
is forcibly freed without checking rdtgrp->waitcount. If at this point
there was a waiter on rdtgrp then a use-after-free issue occurs when the
waiter starts running and accesses the rdtgrp structure it was waiting
on.

See kfree() calls in [1], [2] and [3] in these two call paths in
following scenarios:
(1) rdt_kill_sb() -> rmdir_all_sub() -> free_all_child_rdtgrp()
(2) rdtgroup_rmdir() -> rdtgroup_rmdir_ctrl() -> free_all_child_rdtgrp()

There are several scenarios that result in use-after-free issue in
following:

Scenario 1:
-----------
In Thread 1, rdtgroup_tasks_write() adds a task_work callback
move_myself(). If move_myself() is scheduled to execute after Thread 2
rdt_kill_sb() is finished, referring to earlier rdtgrp memory
(rdtgrp->waitcount) which was already freed in Thread 2 results in
use-after-free issue.

Thread 1 (rdtgroup_tasks_write)        Thread 2 (rdt_kill_sb)
-------------------------------        ----------------------
rdtgroup_kn_lock_live
  atomic_inc(&rdtgrp->waitcount)
  mutex_lock
rdtgroup_move_task
  __rdtgroup_move_task
    /*
     * Take an extra refcount, so rdtgrp cannot be freed
     * before the call back move_myself has been invoked
     */
    atomic_inc(&rdtgrp->waitcount)
    /* Callback move_myself will be scheduled for later */
    task_work_add(move_myself)
rdtgroup_kn_unlock
  mutex_unlock
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
                                       mutex_lock
                                       rmdir_all_sub
                                         /*
                                          * sentry and rdtgrp are freed
                                          * without checking refcount
                                          */
                                         free_all_child_rdtgrp
                                           kfree(sentry)*[1]
                                         kfree(rdtgrp)*[2]
                                       mutex_unlock
/*
 * Callback is scheduled to execute
 * after rdt_kill_sb is finished
 */
move_myself
  /*
   * Use-after-free: refer to earlier rdtgrp
   * memory which was freed in [1] or [2].
   */
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
    kfree(rdtgrp)

Scenario 2:
-----------
In Thread 1, rdtgroup_tasks_write() adds a task_work callback
move_myself(). If move_myself() is scheduled to execute after Thread 2
rdtgroup_rmdir() is finished, referring to earlier rdtgrp memory
(rdtgrp->waitcount) which was already freed in Thread 2 results in
use-after-free issue.

Thread 1 (rdtgroup_tasks_write)        Thread 2 (rdtgroup_rmdir)
-------------------------------        -------------------------
rdtgroup_kn_lock_live
  atomic_inc(&rdtgrp->waitcount)
  mutex_lock
rdtgroup_move_task
  __rdtgroup_move_task
    /*
     * Take an extra refcount, so rdtgrp cannot be freed
     * before the call back move_myself has been invoked
     */
    atomic_inc(&rdtgrp->waitcount)
    /* Callback move_myself will be scheduled for later */
    task_work_add(move_myself)
rdtgroup_kn_unlock
  mutex_unlock
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
                                       rdtgroup_kn_lock_live
                                         atomic_inc(&rdtgrp->waitcount)
                                         mutex_lock
                                       rdtgroup_rmdir_ctrl
                                         free_all_child_rdtgrp
                                           /*
                                            * sentry is freed without
                                            * checking refcount
                                            */
                                           kfree(sentry)*[3]
                                         rdtgroup_ctrl_remove
                                           rdtgrp->flags = RDT_DELETED
                                       rdtgroup_kn_unlock
                                         mutex_unlock
                                         atomic_dec_and_test(
                                                     &rdtgrp->waitcount)
                                         && (flags & RDT_DELETED)
                                           kfree(rdtgrp)
/*
 * Callback is scheduled to execute
 * after rdt_kill_sb is finished
 */
move_myself
  /*
   * Use-after-free: refer to earlier rdtgrp
   * memory which was freed in [3].
   */
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
    kfree(rdtgrp)

If CONFIG_DEBUG_SLAB=y, Slab corruption on kmalloc-2k can be observed
like following. Note that "0x6b" is POISON_FREE after kfree(). The
corrupted bits "0x6a", "0x64" at offset 0x424 correspond to
waitcount member of struct rdtgroup which was freed:

  Slab corruption (Not tainted): kmalloc-2k start=ffff9504c5b0d000, len=2048
  420: 6b 6b 6b 6b 6a 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkjkkkkkkkkkkk
  Single bit error detected. Probably bad RAM.
  Run memtest86+ or a similar memory test tool.
  Next obj: start=ffff9504c5b0d800, len=2048
  000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
  010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk

  Slab corruption (Not tainted): kmalloc-2k start=ffff9504c58ab800, len=2048
  420: 6b 6b 6b 6b 64 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkdkkkkkkkkkkk
  Prev obj: start=ffff9504c58ab000, len=2048
  000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
  010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk

Fix this by taking reference count (waitcount) of rdtgrp into account in
the two call paths that currently do not do so. Instead of always
freeing the resource group it will only be freed if there are no waiters
on it. If there are waiters, the resource group will have its flags set
to RDT_DELETED.

It will be left to the waiter to free the resource group when it starts
running and finding that it was the last waiter and the resource group
has been removed (rdtgrp->flags & RDT_DELETED) since. (1) rdt_kill_sb()
-> rmdir_all_sub() -> free_all_child_rdtgrp() (2) rdtgroup_rmdir() ->
rdtgroup_rmdir_ctrl() -> free_all_child_rdtgrp()

Fixes: f3cbeacaa06e ("x86/intel_rdt/cqm: Add rmdir support")
Fixes: 60cf5e101fd4 ("x86/intel_rdt: Add mkdir to resctrl file system")
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1578500886-21771-2-git-send-email-xiaochen.shen@intel.com
2020-01-20 16:45:43 +01:00
Linus Torvalds
0cc2682d8b Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - a resctrl fix for uninitialized objects found by debugobjects

   - a resctrl memory leak fix

   - fix the unintended re-enabling of the of SME and SEV CPU flags if
     memory encryption was disabled at bootup via the MSR space"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/CPU/AMD: Ensure clearing of SME/SEV features is maintained
  x86/resctrl: Fix potential memory leak
  x86/resctrl: Fix an imbalance in domain_remove_cpu()
2020-01-18 13:02:12 -08:00
Linus Torvalds
a186c112c7 Merge branch 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 RAS fix from Ingo Molnar:
 "Fix a thermal throttling race that can result in easy to trigger boot
  crashes on certain Ice Lake platforms"

* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce/therm_throt: Do not access uninitialized therm_work
2020-01-18 12:56:36 -08:00
Linus Torvalds
b07b9e8d63 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Tooling fixes, three Intel uncore driver fixes, plus an AUX events fix
  uncovered by the perf fuzzer"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Remove PCIe3 unit for SNR
  perf/x86/intel/uncore: Fix missing marker for snr_uncore_imc_freerunning_events
  perf/x86/intel/uncore: Add PCI ID of IMC for Xeon E3 V5 Family
  perf: Correctly handle failed perf_get_aux_event()
  perf hists: Fix variable name's inconsistency in hists__for_each() macro
  perf map: Set kmap->kmaps backpointer for main kernel map chunks
  perf report: Fix incorrectly added dimensions as switch perf data file
  tools lib traceevent: Fix memory leakage in filter_event
2020-01-18 12:55:19 -08:00
Linus Torvalds
e2f73d1e52 Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI fixes from Ingo Molnar:
 "Three EFI fixes:

   - Fix a slow-boot-scrolling regression but making sure we use WC for
     EFI earlycon framebuffer mappings on x86

   - Fix a mixed EFI mode boot crash

   - Disable paging explicitly before entering startup_32() in mixed
     mode bootup"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efistub: Disable paging at mixed mode entry
  efi/libstub/random: Initialize pointer variables to zero for mixed mode
  efi/earlycon: Fix write-combine mapping on x86
2020-01-18 12:50:14 -08:00
Wei Liu
538f127cd3 x86/hyper-v: Add "polling" bit to hv_synic_sint
That bit is documented in TLFS 5.0c as follows:

  Setting the polling bit will have the effect of unmasking an
  interrupt source, except that an actual interrupt is not generated.

Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20191222233404.1629-1-wei.liu@kernel.org
2020-01-17 14:38:21 +01:00
Kan Liang
2167f1625c perf/x86/intel/uncore: Remove PCIe3 unit for SNR
The PCIe Root Port driver for CPU Complex PCIe Root Ports are not
loaded on SNR.

The device ID for SNR PCIe3 unit is used by both uncore driver and the
PCIe Root Port driver. If uncore driver is loaded, the PCIe Root Port
driver never be probed.

Remove the PCIe3 unit for SNR for now. The support for PCIe3 unit will
be added later separately.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200116200210.18937-2-kan.liang@linux.intel.com
2020-01-17 11:33:38 +01:00
Kan Liang
fa694ae532 perf/x86/intel/uncore: Fix missing marker for snr_uncore_imc_freerunning_events
An Oops during the boot is found on some SNR machines.  It turns out
this is because the snr_uncore_imc_freerunning_events[] array was
missing an end-marker.

Fixes: ee49532b38dd ("perf/x86/intel/uncore: Add IMC uncore support for Snow Ridge")
Reported-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Like Xu <like.xu@linux.intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200116200210.18937-1-kan.liang@linux.intel.com
2020-01-17 11:33:28 +01:00
Kan Liang
e743830451 perf/x86/intel/uncore: Add PCI ID of IMC for Xeon E3 V5 Family
The IMC uncore support is missed for E3-1585 v5 CPU.

Intel Xeon E3 V5 Family has Sky Lake CPU.
Add the PCI ID of IMC for Intel Xeon E3 V5 Family.

Reported-by: Rosales-fernandez, Carlos <carlos.rosales-fernandez@intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Rosales-fernandez, Carlos <carlos.rosales-fernandez@intel.com>
Link: https://lkml.kernel.org/r/1578687311-158748-1-git-send-email-kan.liang@linux.intel.com
2020-01-17 11:33:18 +01:00
Tom Lendacky
a006483b2f x86/CPU/AMD: Ensure clearing of SME/SEV features is maintained
If the SME and SEV features are present via CPUID, but memory encryption
support is not enabled (MSR 0xC001_0010[23]), the feature flags are cleared
using clear_cpu_cap(). However, if get_cpu_cap() is later called, these
feature flags will be reset back to present, which is not desired.

Change from using clear_cpu_cap() to setup_clear_cpu_cap() so that the
clearing of the flags is maintained.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org> # 4.16.x-
Link: https://lkml.kernel.org/r/226de90a703c3c0be5a49565047905ac4e94e8f3.1579125915.git.thomas.lendacky@amd.com
2020-01-16 20:23:20 +01:00
Chuansheng Liu
978370956d x86/mce/therm_throt: Do not access uninitialized therm_work
It is relatively easy to trigger the following boot splat on an Ice Lake
client platform. The call stack is like:

  kernel BUG at kernel/timer/timer.c:1152!

  Call Trace:
  __queue_delayed_work
  queue_delayed_work_on
  therm_throt_process
  intel_thermal_interrupt
  ...

The reason is that a CPU's thermal interrupt is enabled prior to
executing its hotplug onlining callback which will initialize the
throttling workqueues.

Such a race can lead to therm_throt_process() accessing an uninitialized
therm_work, leading to the above BUG at a very early bootup stage.

Therefore, unmask the thermal interrupt vector only after having setup
the workqueues completely.

 [ bp: Heavily massage commit message and correct comment formatting. ]

Fixes: f6656208f04e ("x86/mce/therm_throt: Optimize notifications of thermal throttle")
Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200107004116.59353-1-chuansheng.liu@intel.com
2020-01-15 11:31:33 +01:00
Amanieu d'Antras
457677c70c
um: Implement copy_thread_tls
This is required for clone3 which passes the TLS value through a
struct rather than a register.

Signed-off-by: Amanieu d'Antras <amanieu@gmail.com>
Cc: linux-um@lists.infradead.org
Cc: <stable@vger.kernel.org> # 5.3.x
Link: https://lore.kernel.org/r/20200104123928.1048822-1-amanieu@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-01-07 13:31:29 +01:00
David Hildenbrand
feee6b2989 mm/memory_hotplug: shrink zones when offlining memory
We currently try to shrink a single zone when removing memory.  We use
the zone of the first page of the memory we are removing.  If that
memmap was never initialized (e.g., memory was never onlined), we will
read garbage and can trigger kernel BUGs (due to a stale pointer):

    BUG: unable to handle page fault for address: 000000000000353d
    #PF: supervisor write access in kernel mode
    #PF: error_code(0x0002) - not-present page
    PGD 0 P4D 0
    Oops: 0002 [#1] SMP PTI
    CPU: 1 PID: 7 Comm: kworker/u8:0 Not tainted 5.3.0-rc5-next-20190820+ #317
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.4
    Workqueue: kacpi_hotplug acpi_hotplug_work_fn
    RIP: 0010:clear_zone_contiguous+0x5/0x10
    Code: 48 89 c6 48 89 c3 e8 2a fe ff ff 48 85 c0 75 cf 5b 5d c3 c6 85 fd 05 00 00 01 5b 5d c3 0f 1f 840
    RSP: 0018:ffffad2400043c98 EFLAGS: 00010246
    RAX: 0000000000000000 RBX: 0000000200000000 RCX: 0000000000000000
    RDX: 0000000000200000 RSI: 0000000000140000 RDI: 0000000000002f40
    RBP: 0000000140000000 R08: 0000000000000000 R09: 0000000000000001
    R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000140000
    R13: 0000000000140000 R14: 0000000000002f40 R15: ffff9e3e7aff3680
    FS:  0000000000000000(0000) GS:ffff9e3e7bb00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 000000000000353d CR3: 0000000058610000 CR4: 00000000000006e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
     __remove_pages+0x4b/0x640
     arch_remove_memory+0x63/0x8d
     try_remove_memory+0xdb/0x130
     __remove_memory+0xa/0x11
     acpi_memory_device_remove+0x70/0x100
     acpi_bus_trim+0x55/0x90
     acpi_device_hotplug+0x227/0x3a0
     acpi_hotplug_work_fn+0x1a/0x30
     process_one_work+0x221/0x550
     worker_thread+0x50/0x3b0
     kthread+0x105/0x140
     ret_from_fork+0x3a/0x50
    Modules linked in:
    CR2: 000000000000353d

Instead, shrink the zones when offlining memory or when onlining failed.
Introduce and use remove_pfn_range_from_zone(() for that.  We now
properly shrink the zones, even if we have DIMMs whereby

 - Some memory blocks fall into no zone (never onlined)

 - Some memory blocks fall into multiple zones (offlined+re-onlined)

 - Multiple memory blocks that fall into different zones

Drop the zone parameter (with a potential dubious value) from
__remove_pages() and __remove_section().

Link: http://lkml.kernel.org/r/20191006085646.5768-6-david@redhat.com
Fixes: f1dd2cd13c4b ("mm, memory_hotplug: do not associate hotadded memory to zones until online")	[visible after d0dc12e86b319]
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: <stable@vger.kernel.org>	[5.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-04 13:55:08 -08:00
Shakeel Butt
ab6a211443 x86/resctrl: Fix potential memory leak
set_cache_qos_cfg() is leaking memory when the given level is not
RDT_RESOURCE_L3 or RDT_RESOURCE_L2. At the moment, this function is
called with only valid levels but move the allocation after the valid
level checks in order to make it more robust and future proof.

 [ bp: Massage commit message. ]

Fixes: 99adde9b370de ("x86/intel_rdt: Enable L2 CDP in MSR IA32_L2_QOS_CFG")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20200102165844.133133-1-shakeelb@google.com
2020-01-02 18:26:27 +01:00
Qian Cai
e278af89f1 x86/resctrl: Fix an imbalance in domain_remove_cpu()
A system that supports resource monitoring may have multiple resources
while not all of these resources are capable of monitoring. Monitoring
related state is initialized only for resources that are capable of
monitoring and correspondingly this state should subsequently only be
removed from these resources that are capable of monitoring.

domain_add_cpu() calls domain_setup_mon_state() only when r->mon_capable
is true where it will initialize d->mbm_over. However,
domain_remove_cpu() calls cancel_delayed_work(&d->mbm_over) without
checking r->mon_capable resulting in an attempt to cancel d->mbm_over on
all resources, even those that never initialized d->mbm_over because
they are not capable of monitoring. Hence, it triggers a debugobjects
warning when offlining CPUs because those timer debugobjects are never
initialized:

  ODEBUG: assert_init not available (active state 0) object type:
  timer_list hint: 0x0
  WARNING: CPU: 143 PID: 789 at lib/debugobjects.c:484
  debug_print_object
  Hardware name: HP Synergy 680 Gen9/Synergy 680 Gen9 Compute Module, BIOS I40 05/23/2018
  RIP: 0010:debug_print_object
  Call Trace:
  debug_object_assert_init
  del_timer
  try_to_grab_pending
  cancel_delayed_work
  resctrl_offline_cpu
  cpuhp_invoke_callback
  cpuhp_thread_fun
  smpboot_thread_fn
  kthread
  ret_from_fork

Fixes: e33026831bdb ("x86/intel_rdt/mbm: Handle counter overflow")
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: john.stultz@linaro.org
Cc: sboyd@kernel.org
Cc: <stable@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: tj@kernel.org
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191211033042.2188-1-cai@lca.pw
2019-12-30 19:25:59 +01:00
Ard Biesheuvel
4911ee401b x86/efistub: Disable paging at mixed mode entry
The EFI mixed mode entry code goes through the ordinary startup_32()
routine before jumping into the kernel's EFI boot code in 64-bit
mode. The 32-bit startup code must be entered with paging disabled,
but this is not documented as a requirement for the EFI handover
protocol, and so we should disable paging explicitly when entering
the kernel from 32-bit EFI firmware.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: <stable@vger.kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224132909.102540-4-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25 10:46:07 +01:00
Omar Sandoval
8757dc970f x86/crash: Define arch_crash_save_vmcoreinfo() if CONFIG_CRASH_CORE=y
On x86 kernels configured with CONFIG_PROC_KCORE=y and
CONFIG_KEXEC_CORE=n, the vmcoreinfo note in /proc/kcore is incomplete.

Specifically, it is missing arch-specific information like the KASLR
offset and whether 5-level page tables are enabled. This breaks
applications like drgn [1] and crash [2], which need this information
for live debugging via /proc/kcore.

This happens because:

1. CONFIG_PROC_KCORE selects CONFIG_CRASH_CORE.
2. kernel/crash_core.c (compiled if CONFIG_CRASH_CORE=y) calls
   arch_crash_save_vmcoreinfo() to get the arch-specific parts of
   vmcoreinfo. If it is not defined, then it uses a no-op fallback.
3. x86 defines arch_crash_save_vmcoreinfo() in
   arch/x86/kernel/machine_kexec_*.c, which is only compiled if
   CONFIG_KEXEC_CORE=y.

Therefore, an x86 kernel with CONFIG_CRASH_CORE=y and
CONFIG_KEXEC_CORE=n uses the no-op fallback and gets incomplete
vmcoreinfo data. This isn't relevant to kdump, which requires
CONFIG_KEXEC_CORE. It only affects applications which read vmcoreinfo at
runtime, like the ones mentioned above.

Fix it by moving arch_crash_save_vmcoreinfo() into two new
arch/x86/kernel/crash_core_*.c files, which are gated behind
CONFIG_CRASH_CORE.

1: 73dd7def12/libdrgn/program.c (L385)
2: 60a42d7092

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/0589961254102cca23e3618b96541b89f2b249e2.1576858905.git.osandov@fb.com
2019-12-23 12:58:41 +01:00
Linus Torvalds
a313c8e056 PPC:
* Fix a bug where we try to do an ultracall on a system without an ultravisor.
 
 KVM:
 - Fix uninitialised sysreg accessor
 - Fix handling of demand-paged device mappings
 - Stop spamming the console on IMPDEF sysregs
 - Relax mappings of writable memslots
 - Assorted cleanups
 
 MIPS:
 - Now orphan, James Hogan is stepping down
 
 x86:
 - MAINTAINERS change, so long Radim and thanks for all the fish
 - supported CPUID fixes for AMD machines without SPEC_CTRL
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "PPC:
   - Fix a bug where we try to do an ultracall on a system without an
     ultravisor

  KVM:
   - Fix uninitialised sysreg accessor
   - Fix handling of demand-paged device mappings
   - Stop spamming the console on IMPDEF sysregs
   - Relax mappings of writable memslots
   - Assorted cleanups

  MIPS:
   - Now orphan, James Hogan is stepping down

  x86:
   - MAINTAINERS change, so long Radim and thanks for all the fish
   - supported CPUID fixes for AMD machines without SPEC_CTRL"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  MAINTAINERS: remove Radim from KVM maintainers
  MAINTAINERS: Orphan KVM for MIPS
  kvm: x86: Host feature SSBD doesn't imply guest feature AMD_SSBD
  kvm: x86: Host feature SSBD doesn't imply guest feature SPEC_CTRL_SSBD
  KVM: PPC: Book3S HV: Don't do ultravisor calls on systems without ultravisor
  KVM: arm/arm64: Properly handle faulting of device mappings
  KVM: arm64: Ensure 'params' is initialised when looking up sys register
  KVM: arm/arm64: Remove excessive permission check in kvm_arch_prepare_memory_region
  KVM: arm64: Don't log IMP DEF sysreg traps
  KVM: arm64: Sanely ratelimit sysreg messages
  KVM: arm/arm64: vgic: Use wrapper function to lock/unlock all vcpus in kvm_vgic_create()
  KVM: arm/arm64: vgic: Fix potential double free dist->spis in __kvm_vgic_destroy()
  KVM: arm/arm64: Get rid of unused arg in cpu_init_hyp_mode()
2019-12-22 10:26:59 -08:00
Paolo Bonzini
d68321dec1 PPC KVM fix for 5.5
- Fix a bug where we try to do an ultracall on a system without an
   ultravisor.
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Merge tag 'kvm-ppc-fixes-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-master

PPC KVM fix for 5.5

- Fix a bug where we try to do an ultracall on a system without an
  ultravisor.
2019-12-22 13:18:15 +01:00
Linus Torvalds
c4ff10efe8 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Misc fixes: a BTS fix, a PT NMI handling fix, a PMU sysfs fix and an
  SRCU annotation"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Add SRCU annotation for pmus list walk
  perf/x86/intel: Fix PT PMI handling
  perf/x86/intel/bts: Fix the use of page_private()
  perf/x86: Fix potential out-of-bounds access
2019-12-21 10:51:00 -08:00
Linus Torvalds
6c1c79a5f4 Kbuild fixes for v5.5
- fix warning in out-of-tree 'make clean'
 
  - add READELF variable to the top Makefile
 
  - fix broken builds when LINUX_COMPILE_BY contains a backslash
 
  - fix build warning in kallsyms
 
  - fix NULL pointer access in expr_eq() in Kconfig
 
  - fix missing dependency on rsync in deb-pkg build
 
  - remove ---help--- from documentation
 
  - fix misleading documentation about directory descending
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Merge tag 'kbuild-fixes-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - fix warning in out-of-tree 'make clean'

 - add READELF variable to the top Makefile

 - fix broken builds when LINUX_COMPILE_BY contains a backslash

 - fix build warning in kallsyms

 - fix NULL pointer access in expr_eq() in Kconfig

 - fix missing dependency on rsync in deb-pkg build

 - remove ---help--- from documentation

 - fix misleading documentation about directory descending

* tag 'kbuild-fixes-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: clarify the difference between obj-y and obj-m w.r.t. descending
  kconfig: remove ---help--- from documentation
  scripts: package: mkdebian: add missing rsync dependency
  kconfig: don't crash on NULL expressions in expr_eq()
  scripts/kallsyms: fix offset overflow of kallsyms_relative_base
  mkcompile_h: use printf for LINUX_COMPILE_BY
  mkcompile_h: git rid of UTS_TRUNCATE from LINUX_COMPILE_{BY,HOST}
  x86/boot: kbuild: allow readelf executable to be specified
  kbuild: fix 'No such file or directory' warning when cleaning
2019-12-21 10:49:47 -08:00
Linus Torvalds
5c741e2583 Merge branch 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 RAS fixes from Borislav Petkov:
 "Three urgent RAS fixes for the AMD side of things:

   - initialize struct mce.bank so that calculated error severity on AMD
     SMCA machines is correct

   - do not send IPIs early during bank initialization, when interrupts
     are disabled

   - a fix for when only a subset of MCA banks are enabled, which led to
     boot hangs on some new AMD CPUs"

* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Fix possibly incorrect severity calculation on AMD
  x86/MCE/AMD: Allow Reserved types to be overwritten in smca_banks[]
  x86/MCE/AMD: Do not use rdmsr_safe_on_cpu() in smca_configure()
2019-12-21 06:04:12 -08:00
Jim Mattson
8715f05269 kvm: x86: Host feature SSBD doesn't imply guest feature AMD_SSBD
The host reports support for the synthetic feature X86_FEATURE_SSBD
when any of the three following hardware features are set:
  CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31]
  CPUID.80000008H:EBX.AMD_SSBD[bit 24]
  CPUID.80000008H:EBX.VIRT_SSBD[bit 25]

Either of the first two hardware features implies the existence of the
IA32_SPEC_CTRL MSR, but CPUID.80000008H:EBX.VIRT_SSBD[bit 25] does
not. Therefore, CPUID.80000008H:EBX.AMD_SSBD[bit 24] should only be
set in the guest if CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] or
CPUID.80000008H:EBX.AMD_SSBD[bit 24] is set on the host.

Fixes: 4c6903a0f9d76 ("KVM: x86: fix reporting of AMD speculation bug CPUID leaf")
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Jacob Xu <jacobhxu@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Reported-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-12-18 17:46:35 +01:00
Jim Mattson
396d2e878f kvm: x86: Host feature SSBD doesn't imply guest feature SPEC_CTRL_SSBD
The host reports support for the synthetic feature X86_FEATURE_SSBD
when any of the three following hardware features are set:
  CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31]
  CPUID.80000008H:EBX.AMD_SSBD[bit 24]
  CPUID.80000008H:EBX.VIRT_SSBD[bit 25]

Either of the first two hardware features implies the existence of the
IA32_SPEC_CTRL MSR, but CPUID.80000008H:EBX.VIRT_SSBD[bit 25] does
not. Therefore, CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] should only be
set in the guest if CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] or
CPUID.80000008H:EBX.AMD_SSBD[bit 24] is set on the host.

Fixes: 0c54914d0c52a ("KVM: x86: use Intel speculation bugs and features as derived in generic x86 code")
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Jacob Xu <jacobhxu@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Reported-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-12-18 17:46:23 +01:00
Linus Torvalds
9065e06360 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Ingo Molnar:
 "Fix kexec booting with certain EFI memory map layouts"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efi: Update e820 with reserved EFI boot services data to fix kexec breakage
2019-12-17 11:17:03 -08:00
Linus Torvalds
2abf193275 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Ingo Molnar:
 "Add HPET quirks for the Intel 'Coffee Lake H' and 'Ice Lake' platforms"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel: Disable HPET on Intel Ice Lake platforms
  x86/intel: Disable HPET on Intel Coffee Lake H platforms
2019-12-17 11:11:08 -08:00
Alexander Shishkin
92ca7da4bd perf/x86/intel: Fix PT PMI handling
Commit:

  ccbebba4c6bf ("perf/x86/intel/pt: Bypass PT vs. LBR exclusivity if the core supports it")

skips the PT/LBR exclusivity check on CPUs where PT and LBRs coexist, but
also inadvertently skips the active_events bump for PT in that case, which
is a bug. If there aren't any hardware events at the same time as PT, the
PMI handler will ignore PT PMIs, as active_events reads zero in that case,
resulting in the "Uhhuh" spurious NMI warning and PT data loss.

Fix this by always increasing active_events for PT events.

Fixes: ccbebba4c6bf ("perf/x86/intel/pt: Bypass PT vs. LBR exclusivity if the core supports it")
Reported-by: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lkml.kernel.org/r/20191210105101.77210-1-alexander.shishkin@linux.intel.com
2019-12-17 13:32:46 +01:00
Alexander Shishkin
ff61541cc6 perf/x86/intel/bts: Fix the use of page_private()
Commit

  8062382c8dbe2 ("perf/x86/intel/bts: Add BTS PMU driver")

brought in a warning with the BTS buffer initialization
that is easily tripped with (assuming KPTI is disabled):

instantly throwing:

> ------------[ cut here ]------------
> WARNING: CPU: 2 PID: 326 at arch/x86/events/intel/bts.c:86 bts_buffer_setup_aux+0x117/0x3d0
> Modules linked in:
> CPU: 2 PID: 326 Comm: perf Not tainted 5.4.0-rc8-00291-gceb9e77324fa #904
> RIP: 0010:bts_buffer_setup_aux+0x117/0x3d0
> Call Trace:
>  rb_alloc_aux+0x339/0x550
>  perf_mmap+0x607/0xc70
>  mmap_region+0x76b/0xbd0
...

It appears to assume (for lost raisins) that PagePrivate() is set,
while later it actually tests for PagePrivate() before using
page_private().

Make it consistent and always check PagePrivate() before using
page_private().

Fixes: 8062382c8dbe2 ("perf/x86/intel/bts: Add BTS PMU driver")
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lkml.kernel.org/r/20191205142853.28894-2-alexander.shishkin@linux.intel.com
2019-12-17 13:32:46 +01:00
Peter Zijlstra
1e69a0efc0 perf/x86: Fix potential out-of-bounds access
UBSAN reported out-of-bound accesses for x86_pmu.event_map(), it's
arguments should be < x86_pmu.max_events. Make sure all users observe
this constraint.

Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Meelis Roos <mroos@linux.ee>
2019-12-17 13:32:46 +01:00
Jan H. Schönherr
a3a57ddad0 x86/mce: Fix possibly incorrect severity calculation on AMD
The function mce_severity_amd_smca() requires m->bank to be initialized
for correct operation. Fix the one case, where mce_severity() is called
without doing so.

Fixes: 6bda529ec42e ("x86/mce: Grade uncorrected errors for SMCA-enabled systems")
Fixes: d28af26faa0b ("x86/MCE: Initialize mce.bank in the case of a fatal error in mce_no_way_out()")
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: <stable@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: Yazen Ghannam <Yazen.Ghannam@amd.com>
Link: https://lkml.kernel.org/r/20191210000733.17979-4-jschoenh@amazon.de
2019-12-17 09:39:53 +01:00
Yazen Ghannam
966af20929 x86/MCE/AMD: Allow Reserved types to be overwritten in smca_banks[]
Each logical CPU in Scalable MCA systems controls a unique set of MCA
banks in the system. These banks are not shared between CPUs. The bank
types and ordering will be the same across CPUs on currently available
systems.

However, some CPUs may see a bank as Reserved/Read-as-Zero (RAZ) while
other CPUs do not. In this case, the bank seen as Reserved on one CPU is
assumed to be the same type as the bank seen as a known type on another
CPU.

In general, this occurs when the hardware represented by the MCA bank
is disabled, e.g. disabled memory controllers on certain models, etc.
The MCA bank is disabled in the hardware, so there is no possibility of
getting an MCA/MCE from it even if it is assumed to have a known type.

For example:

Full system:
	Bank  |  Type seen on CPU0  |  Type seen on CPU1
	------------------------------------------------
	 0    |         LS          |          LS
	 1    |         UMC         |          UMC
	 2    |         CS          |          CS

System with hardware disabled:
	Bank  |  Type seen on CPU0  |  Type seen on CPU1
	------------------------------------------------
	 0    |         LS          |          LS
	 1    |         UMC         |          RAZ
	 2    |         CS          |          CS

For this reason, there is a single, global struct smca_banks[] that is
initialized at boot time. This array is initialized on each CPU as it
comes online. However, the array will not be updated if an entry already
exists.

This works as expected when the first CPU (usually CPU0) has all
possible MCA banks enabled. But if the first CPU has a subset, then it
will save a "Reserved" type in smca_banks[]. Successive CPUs will then
not be able to update smca_banks[] even if they encounter a known bank
type.

This may result in unexpected behavior. Depending on the system
configuration, a user may observe issues enumerating the MCA
thresholding sysfs interface. The issues may be as trivial as sysfs
entries not being available, or as severe as system hangs.

For example:

	Bank  |  Type seen on CPU0  |  Type seen on CPU1
	------------------------------------------------
	 0    |         LS          |          LS
	 1    |         RAZ         |          UMC
	 2    |         CS          |          CS

Extend the smca_banks[] entry check to return if the entry is a
non-reserved type. Otherwise, continue so that CPUs that encounter a
known bank type can update smca_banks[].

Fixes: 68627a697c19 ("x86/mce/AMD, EDAC/mce_amd: Enumerate Reserved SMCA bank type")
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: <stable@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191121141508.141273-1-Yazen.Ghannam@amd.com
2019-12-17 09:39:53 +01:00
Konstantin Khlebnikov
246ff09f89 x86/MCE/AMD: Do not use rdmsr_safe_on_cpu() in smca_configure()
... because interrupts are disabled that early and sending IPIs can
deadlock:

  BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
  in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1
  no locks held by swapper/1/0.
  irq event stamp: 0
  hardirqs last  enabled at (0): [<0000000000000000>] 0x0
  hardirqs last disabled at (0): [<ffffffff8106dda9>] copy_process+0x8b9/0x1ca0
  softirqs last  enabled at (0): [<ffffffff8106dda9>] copy_process+0x8b9/0x1ca0
  softirqs last disabled at (0): [<0000000000000000>] 0x0
  Preemption disabled at:
  [<ffffffff8104703b>] start_secondary+0x3b/0x190
  CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.5.0-rc2+ #1
  Hardware name: GIGABYTE MZ01-CE1-00/MZ01-CE1-00, BIOS F02 08/29/2018
  Call Trace:
   dump_stack
   ___might_sleep.cold.92
   wait_for_completion
   ? generic_exec_single
   rdmsr_safe_on_cpu
   ? wrmsr_on_cpus
   mce_amd_feature_init
   mcheck_cpu_init
   identify_cpu
   identify_secondary_cpu
   smp_store_cpu_info
   start_secondary
   secondary_startup_64

The function smca_configure() is called only on the current CPU anyway,
therefore replace rdmsr_safe_on_cpu() with atomic rdmsr_safe() and avoid
the IPI.

 [ bp: Update commit message. ]

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: <stable@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/157252708836.3876.4604398213417262402.stgit@buzz
2019-12-17 09:39:33 +01:00
Dmitry Golovin
eefb8c124f x86/boot: kbuild: allow readelf executable to be specified
Introduce a new READELF variable to top-level Makefile, so the name of
readelf binary can be specified.

Before this change the name of the binary was hardcoded to
"$(CROSS_COMPILE)readelf" which might not be present for every
toolchain.

This allows to build with LLVM Object Reader by using make parameter
READELF=llvm-readelf.

Link: https://github.com/ClangBuiltLinux/linux/issues/771
Signed-off-by: Dmitry Golovin <dima@golovin.in>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2019-12-14 15:53:04 +09:00
Linus Torvalds
22ff311af9 treewide conversion from FIELD_SIZEOF() to sizeof_field()
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Merge tag 'sizeof_field-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull FIELD_SIZEOF conversion from Kees Cook:
 "A mostly mechanical treewide conversion from FIELD_SIZEOF() to
  sizeof_field(). This avoids the redundancy of having 2 macros
  (actually 3) doing the same thing, and consolidates on sizeof_field().
  While "field" is not an accurate name, it is the common name used in
  the kernel, and doesn't result in any unintended innuendo.

  As there are still users of FIELD_SIZEOF() in -next, I will clean up
  those during this coming development cycle and send the final old
  macro removal patch at that time"

* tag 'sizeof_field-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  treewide: Use sizeof_field() macro
  MIPS: OCTEON: Replace SIZEOF_FIELD() macro
2019-12-13 14:02:12 -08:00
Linus Torvalds
6674fdb25a This contains 3 changes:
- Removal of code I accidentally applied when doing a minor fix up
    to a patch, and then using "git commit -a --amend", which pulled
    in some other changes I was playing with.
 
  - Remove an used variable in trace_events_inject code
 
  - Fix to function graph tracer when it traces a ftrace direct function.
    It will now ignore tracing a function that has a ftrace direct
    tramploine attached. This is needed for eBPF to use the ftrace direct
    code.
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Merge tag 'trace-v5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Remove code I accidentally applied when doing a minor fix up to a
   patch, and then using "git commit -a --amend", which pulled in some
   other changes I was playing with.

 - Remove an used variable in trace_events_inject code

 - Fix function graph tracer when it traces a ftrace direct function.
   It will now ignore tracing a function that has a ftrace direct
   tramploine attached. This is needed for eBPF to use the ftrace direct
   code.

* tag 'trace-v5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix function_graph tracer interaction with BPF trampoline
  tracing: remove set but not used variable 'buffer'
  module: Remove accidental change of module_enable_x()
2019-12-11 12:22:38 -08:00
Alexei Starovoitov
ff205766db ftrace: Fix function_graph tracer interaction with BPF trampoline
Depending on type of BPF programs served by BPF trampoline it can call original
function. In such case the trampoline will skip one stack frame while
returning. That will confuse function_graph tracer and will cause crashes with
bad RIP. Teach graph tracer to skip functions that have BPF trampoline attached.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-12-10 13:53:59 -05:00
Pankaj Bharadiya
c593642c8b treewide: Use sizeof_field() macro
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except
at places where these are defined. Later patches will remove the unused
definition of FIELD_SIZEOF().

This patch is generated using following script:

EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h"

git grep -l -e "\bFIELD_SIZEOF\b" | while read file;
do

	if [[ "$file" =~ $EXCLUDE_FILES ]]; then
		continue
	fi
	sed -i  -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file;
done

Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David Miller <davem@davemloft.net> # for net
2019-12-09 10:36:44 -08:00
Linus Torvalds
43a2898631 powerpc updates for 5.5 #2
A few commits splitting the KASAN instrumented bitops header in
 three, to match the split of the asm-generic bitops headers.
 
 This is needed on powerpc because we use asm-generic/bitops/non-atomic.h,
 for the non-atomic bitops, whereas the existing KASAN instrumented
 bitops assume all the underlying operations are provided by the arch
 as arch_foo() versions.
 
 Thanks to:
   Daniel Axtens & Christophe Leroy.
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Merge tag 'powerpc-5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull more powerpc updates from Michael Ellerman:
 "A few commits splitting the KASAN instrumented bitops header in three,
  to match the split of the asm-generic bitops headers.

  This is needed on powerpc because we use the generic bitops for the
  non-atomic case only, whereas the existing KASAN instrumented bitops
  assume all the underlying operations are provided by the arch as
  arch_foo() versions.

  Thanks to: Daniel Axtens & Christophe Leroy"

* tag 'powerpc-5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  docs/core-api: Remove possibly confusing sub-headings from Bit Operations
  powerpc: support KASAN instrumentation of bitops
  kasan: support instrumented bitops combined with generic bitops
2019-12-06 13:36:31 -08:00
Linus Torvalds
5ecc9d15f7 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "Most of the rest of MM and various other things. Some Kconfig rework
  still awaits merges of dependent trees from linux-next.

  Subsystems affected by this patch series: mm/hotfixes, mm/memcg,
  mm/vmstat, mm/thp, procfs, sysctl, misc, notifiers, core-kernel,
  bitops, lib, checkpatch, epoll, binfmt, init, rapidio, uaccess, kcov,
  ubsan, ipc, bitmap, mm/pagemap"

* akpm: (86 commits)
  mm: remove __ARCH_HAS_4LEVEL_HACK and include/asm-generic/4level-fixup.h
  um: add support for folded p4d page tables
  um: remove unused pxx_offset_proc() and addr_pte() functions
  sparc32: use pgtable-nopud instead of 4level-fixup
  parisc/hugetlb: use pgtable-nopXd instead of 4level-fixup
  parisc: use pgtable-nopXd instead of 4level-fixup
  nds32: use pgtable-nopmd instead of 4level-fixup
  microblaze: use pgtable-nopmd instead of 4level-fixup
  m68k: mm: use pgtable-nopXd instead of 4level-fixup
  m68k: nommu: use pgtable-nopud instead of 4level-fixup
  c6x: use pgtable-nopud instead of 4level-fixup
  arm: nommu: use pgtable-nopud instead of 4level-fixup
  alpha: use pgtable-nopud instead of 4level-fixup
  gpio: pca953x: tighten up indentation
  gpio: pca953x: convert to use bitmap API
  gpio: pca953x: use input from regs structure in pca953x_irq_pending()
  gpio: pca953x: remove redundant variable and check in IRQ handler
  lib/bitmap: introduce bitmap_replace() helper
  lib/test_bitmap: fix comment about this file
  lib/test_bitmap: move exp1 and exp2 upper for others to use
  ...
2019-12-05 09:46:26 -08:00
Masahiro Yamada
0fb9dc2867 arch: sembuf.h: make uapi asm/sembuf.h self-contained
Userspace cannot compile <asm/sembuf.h> due to some missing type
definitions.  For example, building it for x86 fails as follows:

    CC      usr/include/asm/sembuf.h.s
  In file included from <command-line>:32:0:
  usr/include/asm/sembuf.h:17:20: error: field `sem_perm' has incomplete type
    struct ipc64_perm sem_perm; /* permissions .. see ipc.h */
                      ^~~~~~~~
  usr/include/asm/sembuf.h:24:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t sem_otime; /* last semop time */
    ^~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:25:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused1;
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:26:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t sem_ctime; /* last change time */
    ^~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:27:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused2;
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:29:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t sem_nsems; /* no. of semaphores in array */
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:30:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused3;
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:31:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused4;
    ^~~~~~~~~~~~~~~~

It is just a matter of missing include directive.

Include <asm/ipcbuf.h> to make it self-contained, and add it to
the compile-test coverage.

Link: http://lkml.kernel.org/r/20191030063855.9989-3-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-04 19:44:14 -08:00