Commit graph

61 commits

Author SHA1 Message Date
Ganesh Goudar
3a1e92d089 powerpc/mce: Fix access error in mce handler
We queue an irq work for deferred processing of mce event in realmode
mce handler, where translation is disabled. Queuing of the work may
result in accessing memory outside RMO region, such access needs the
translation to be enabled for an LPAR running with hash mmu else the
kernel crashes.

After enabling translation in mce_handle_error() we used to leave it
enabled to avoid crashing here, but now with the commit
74c3354bc1 ("powerpc/pseries/mce: restore msr before returning from
handler") we are restoring the MSR to disable translation.

Hence to fix this enable the translation before queuing the work.

Without this change following trace is seen on injecting SLB multihit in
an LPAR running with hash mmu.

  Oops: Kernel access of bad area, sig: 11 [#1]
  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
  CPU: 5 PID: 1883 Comm: insmod Tainted: G        OE     5.14.0-mce+ #137
  NIP:  c000000000735d60 LR: c000000000318640 CTR: 0000000000000000
  REGS: c00000001ebff9a0 TRAP: 0300   Tainted: G       OE      (5.14.0-mce+)
  MSR:  8000000000001003 <SF,ME,RI,LE>  CR: 28008228  XER: 00000001
  CFAR: c00000000031863c DAR: c00000027fa8fe08 DSISR: 40000000 IRQMASK: 0
  ...
  NIP llist_add_batch+0x0/0x40
  LR  __irq_work_queue_local+0x70/0xc0
  Call Trace:
    0xc00000001ebffc0c (unreliable)
    irq_work_queue+0x40/0x70
    machine_check_queue_event+0xbc/0xd0
    machine_check_early_common+0x16c/0x1f4

Fixes: 74c3354bc1 ("powerpc/pseries/mce: restore msr before returning from handler")
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
[mpe: Fix comment formatting, trim oops in change log for readability]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210909064330.312432-1-ganeshgr@linux.ibm.com
2021-09-13 22:34:12 +10:00
Linus Torvalds
019b3fd94b powerpc updates for 5.14
- A big series refactoring parts of our KVM code, and converting some to C.
 
  - Support for ARCH_HAS_SET_MEMORY, and ARCH_HAS_STRICT_MODULE_RWX on some CPUs.
 
  - Support for the Microwatt soft-core.
 
  - Optimisations to our interrupt return path on 64-bit.
 
  - Support for userspace access to the NX GZIP accelerator on PowerVM on Power10.
 
  - Enable KUAP and KUEP by default on 32-bit Book3S CPUs.
 
  - Other smaller features, fixes & cleanups.
 
 Thanks to: Andy Shevchenko, Aneesh Kumar K.V, Arnd Bergmann, Athira Rajeev, Baokun Li,
 Benjamin Herrenschmidt, Bharata B Rao, Christophe Leroy, Daniel Axtens, Daniel Henrique
 Barboza, Finn Thain, Geoff Levand, Haren Myneni, Jason Wang, Jiapeng Chong, Joel Stanley,
 Jordan Niethe, Kajol Jain, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas
 Piggin, Nick Desaulniers, Paul Mackerras, Russell Currey, Sathvika Vasireddy, Shaokun
 Zhang, Stephen Rothwell, Sudeep Holla, Suraj Jitindar Singh, Tom Rix, Vaibhav Jain,
 YueHaibing, Zhang Jianhua, Zhen Lei.
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Merge tag 'powerpc-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - A big series refactoring parts of our KVM code, and converting some
   to C.

 - Support for ARCH_HAS_SET_MEMORY, and ARCH_HAS_STRICT_MODULE_RWX on
   some CPUs.

 - Support for the Microwatt soft-core.

 - Optimisations to our interrupt return path on 64-bit.

 - Support for userspace access to the NX GZIP accelerator on PowerVM on
   Power10.

 - Enable KUAP and KUEP by default on 32-bit Book3S CPUs.

 - Other smaller features, fixes & cleanups.

Thanks to: Andy Shevchenko, Aneesh Kumar K.V, Arnd Bergmann, Athira
Rajeev, Baokun Li, Benjamin Herrenschmidt, Bharata B Rao, Christophe
Leroy, Daniel Axtens, Daniel Henrique Barboza, Finn Thain, Geoff Levand,
Haren Myneni, Jason Wang, Jiapeng Chong, Joel Stanley, Jordan Niethe,
Kajol Jain, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas
Piggin, Nick Desaulniers, Paul Mackerras, Russell Currey, Sathvika
Vasireddy, Shaokun Zhang, Stephen Rothwell, Sudeep Holla, Suraj Jitindar
Singh, Tom Rix, Vaibhav Jain, YueHaibing, Zhang Jianhua, and Zhen Lei.

* tag 'powerpc-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (218 commits)
  powerpc: Only build restart_table.c for 64s
  powerpc/64s: move ret_from_fork etc above __end_soft_masked
  powerpc/64s/interrupt: clean up interrupt return labels
  powerpc/64/interrupt: add missing kprobe annotations on interrupt exit symbols
  powerpc/64: enable MSR[EE] in irq replay pt_regs
  powerpc/64s/interrupt: preserve regs->softe for NMI interrupts
  powerpc/64s: add a table of implicit soft-masked addresses
  powerpc/64e: remove implicit soft-masking and interrupt exit restart logic
  powerpc/64e: fix CONFIG_RELOCATABLE build warnings
  powerpc/64s: fix hash page fault interrupt handler
  powerpc/4xx: Fix setup_kuep() on SMP
  powerpc/32s: Fix setup_{kuap/kuep}() on SMP
  powerpc/interrupt: Use names in check_return_regs_valid()
  powerpc/interrupt: Also use exit_must_hard_disable() on PPC32
  powerpc/sysfs: Replace sizeof(arr)/sizeof(arr[0]) with ARRAY_SIZE
  powerpc/ptrace: Refactor regs_set_return_{msr/ip}
  powerpc/ptrace: Move set_return_regs_changed() before regs_set_return_{msr/ip}
  powerpc/stacktrace: Fix spurious "stale" traces in raise_backtrace_ipi()
  powerpc/pseries/vas: Include irqdomain.h
  powerpc: mark local variables around longjmp as volatile
  ...
2021-07-02 12:54:34 -07:00
Nicholas Piggin
59dc5bfca0 powerpc/64s: avoid reloading (H)SRR registers if they are still valid
When an interrupt is taken, the SRR registers are set to return to where
it left off. Unless they are modified in the meantime, or the return
address or MSR are modified, there is no need to reload these registers
when returning from interrupt.

Introduce per-CPU flags that track the validity of SRR and HSRR
registers. These are cleared when returning from interrupt, when
using the registers for something else (e.g., OPAL calls), when
adjusting the return address or MSR of a context, and when context
switching (which changes the return address and MSR).

This improves the performance of interrupt returns.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fold in fixup patch from Nick]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210617155116.2167984-5-npiggin@gmail.com
2021-06-25 00:06:55 +10:00
Marc Zyngier
13a9a5d17d powerpc: Add missing linux/{of.h,irqdomain.h} include directives
A bunch of PPC files are missing the inclusion of linux/of.h and
linux/irqdomain.h, relying on transitive inclusion from another
file.

As we are about to break this dependency, make sure these dependencies
are explicit.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10 13:09:16 +01:00
Ganesh Goudar
92d9d61be5 powerpc/mce: save ignore_event flag unconditionally for UE
When we hit an UE while using machine check safe copy routines,
ignore_event flag is set and the event is ignored by mce handler,
And the flag is also saved for defered handling and printing of
mce event information, But as of now saving of this flag is done
on checking if the effective address is provided or physical address
is calculated, which is not right.

Save ignore_event flag regardless of whether the effective address is
provided or physical address is calculated.

Without this change following log is seen, when the event is to be
ignored.

[  512.971365] MCE: CPU1: machine check (Severe)  UE Load/Store [Recovered]
[  512.971509] MCE: CPU1: NIP: [c0000000000b67c0] memcpy+0x40/0x90
[  512.971655] MCE: CPU1: Initiator CPU
[  512.971739] MCE: CPU1: Unknown
[  512.972209] MCE: CPU1: machine check (Severe)  UE Load/Store [Recovered]
[  512.972334] MCE: CPU1: NIP: [c0000000000b6808] memcpy+0x88/0x90
[  512.972456] MCE: CPU1: Initiator CPU
[  512.972534] MCE: CPU1: Unknown

Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Reviewed-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210407045816.352276-1-ganeshgr@linux.ibm.com
2021-04-21 22:52:32 +10:00
Li Huafei
f6f1f48e8b powerpc/mce: Make symbol 'mce_ue_event_work' static
The sparse tool complains as follows:

arch/powerpc/kernel/mce.c:43:1: warning:
 symbol 'mce_ue_event_work' was not declared. Should it be static?

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

Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210408035802.31853-1-lihuafei1@huawei.com
2021-04-14 23:04:13 +10:00
Nicholas Piggin
118178e62e powerpc: move NMI entry/exit code into wrapper
This moves the common NMI entry and exit code into the interrupt handler
wrappers.

This changes the behaviour of soft-NMI (watchdog) and HMI interrupts, and
also MCE interrupts on 64e, by adding missing parts of the NMI entry to
them.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-40-npiggin@gmail.com
2021-02-09 00:10:50 +11:00
Nicholas Piggin
3a96570ffc powerpc: convert interrupt handlers to use wrappers
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-29-npiggin@gmail.com
2021-02-09 00:02:12 +11:00
Ganesh Goudar
923b3cf00b powerpc/mce: Remove per cpu variables from MCE handlers
Access to per-cpu variables requires translation to be enabled on
pseries machine running in hash mmu mode, Since part of MCE handler
runs in realmode and part of MCE handling code is shared between ppc
architectures pseries and powernv, it becomes difficult to manage
these variables differently on different architectures, So have
these variables in paca instead of having them as per-cpu variables
to avoid complications.

Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210128104143.70668-2-ganeshgr@linux.ibm.com
2021-01-31 22:35:49 +11:00
Cédric Le Goater
1cc2fd7593 powerpc/mce: Include prototypes
It fixes these W=1 compile errors :

../arch/powerpc/kernel/mce.c:591:14: error: no previous prototype for ‘machine_check_early’ [-Werror=missing-prototypes]
  591 | long notrace machine_check_early(struct pt_regs *regs)
      |              ^~~~~~~~~~~~~~~~~~~
../arch/powerpc/kernel/mce.c:725:6: error: no previous prototype for ‘hmi_exception_realmode’ [-Werror=missing-prototypes]
  725 | long hmi_exception_realmode(struct pt_regs *regs)
      |      ^~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210104143206.695198-8-clg@kaod.org
2021-01-30 11:39:29 +11:00
Nicholas Piggin
4a869531dd powerpc/64s: Remove "Host" from MCE logging
"Host" caused machine check is printed when the kernel sees a MCE
hit in this kernel or userspace, and "Guest" if it hit one of its
guests. This is confusing when a guest kernel handles a hypervisor-
delivered MCE, it also prints "Host".

Just remove "Host". "Guest" is adequate to make the distinction.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-8-npiggin@gmail.com
2020-12-04 01:01:23 +11:00
Nicholas Piggin
0ce2382657 powerpc/64s/powernv: Allow KVM to handle guest machine check details
KVM has strategies to perform machine check recovery. If a MCE hits
in a guest, have the low level handler just decode and save the MCE
but not try to recover anything, so KVM can deal with it.

The host does not own SLBs and does not need to report the SLB state
in case of a multi-hit for example, or know about the virtual memory
map of the guest.

UE and memory poisoning of guest pages in the host is one thing that
is possibly not completely robust at the moment, but this too needs
to go via KVM (possibly via the guest and back out to host via hcall)
rather than being handled at a low level in the host handler.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-3-npiggin@gmail.com
2020-12-04 01:01:22 +11:00
Ganesh Goudar
8d0e210127 powerpc/mce: Avoid nmi_enter/exit in real mode on pseries hash
Use of nmi_enter/exit in real mode handler causes the kernel to panic
and reboot on injecting SLB mutihit on pseries machine running in hash
MMU mode, because these calls try to accesses memory outside RMO
region in real mode handler where translation is disabled.

Add check to not to use these calls on pseries machine running in hash
MMU mode.

Fixes: 116ac378bb ("powerpc/64s: machine check interrupt update NMI accounting")
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201009064005.19777-2-ganeshgr@linux.ibm.com
2020-10-16 20:13:55 +11:00
Mahesh Salgaonkar
ada68a66b7 powerpc/64s: Move HMI IRQ stat from percpu variable to paca.
With the proposed change in percpu bootmem allocator to use page
mapping [1], the percpu first chunk memory area can come from vmalloc
ranges. This makes the HMI (Hypervisor Maintenance Interrupt) handler
crash the kernel whenever percpu variable is accessed in real mode.
This patch fixes this issue by moving the HMI IRQ stat inside paca for
safe access in realmode.

[1] https://lore.kernel.org/linuxppc-dev/20200608070904.387440-1-aneesh.kumar@linux.ibm.com/

Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/159290806973.3642154.5244613424529764050.stgit@jupiter
2020-07-29 23:47:53 +10:00
Nicholas Piggin
201220bb0e powerpc/powernv: Machine check handler for POWER10
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200702233343.1128026-1-npiggin@gmail.com
2020-07-23 17:43:30 +10:00
Santosh Sivaraj
c37a63afc4 powerpc/mce: Add MCE notification chain
Introduce notification chain which lets us know about uncorrected memory
errors(UE). This would help prospective users in pmem or nvdimm subsystem
to track bad blocks for better handling of persistent memory allocations.

Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200709135142.721504-1-santosh@fossix.org
2020-07-20 22:57:56 +10:00
Nicholas Piggin
abd106fb43 powerpc/64s: machine check do not trace real-mode handler
Rather than notrace annotations throughout a significant part of the
machine check code across kernel/ pseries/ and powernv/ which can
easily be broken and is infrequently tested, use paca->ftrace_enabled
to blanket-disable tracing of the real-mode non-maskable handler.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Link: https://lore.kernel.org/r/20200508043408.886394-14-npiggin@gmail.com
2020-05-19 00:10:34 +10:00
Nicholas Piggin
116ac378bb powerpc/64s: machine check interrupt update NMI accounting
machine_check_early() is taken as an NMI, so nmi_enter() is used
there. machine_check_exception() is no longer taken as an NMI (it's
invoked via irq_work in the case a machine check hits in kernel mode),
so remove the nmi_enter() from that case.

In NMI context, hash faults don't try to refill the hash table, which
can lead to crashes accessing non-pinned kernel pages. System reset
still has this potential problem.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Drop change in show_regs() which breaks Book3E]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200508043408.886394-12-npiggin@gmail.com
2020-05-19 00:10:34 +10:00
Ganesh Goudar
efbc4303b2 powerpc/pseries: Handle UE event for memcpy_mcsafe
memcpy_mcsafe has been implemented for power machines which is used
by pmem infrastructure, so that an UE encountered during memcpy from
pmem devices would not result in panic instead a right error code
is returned. The implementation expects machine check handler to ignore
the event and set nip to continue the execution from fixup code.

Appropriate changes are already made to powernv machine check handler,
make similar changes to pseries machine check handler to ignore the
the event and set nip to continue execution at the fixup entry if we
hit UE at an instruction with a fixup entry.

while we are at it, have a common function which searches the exception
table entry and updates nip with fixup address, and any future common
changes can be made in this function that are valid for both architectures.

powernv changes are made by
commit 895e3dceeb ("powerpc/mce: Handle UE event for memcpy_mcsafe")

Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reviewed-by: Santosh S <santosh@fossix.org>
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200326184916.31172-1-ganeshgr@linux.ibm.com
2020-03-27 14:59:35 +11:00
Nicholas Piggin
9ca766f989 powerpc/64s/pseries: machine check convert to use common event code
The common machine_check_event data structures and queues are mostly
platform independent, with powernv decoding SRR1/DSISR/etc., into
machine_check_event objects.

This patch converts pseries to use this infrastructure by decoding
fwnmi/rtas data into machine_check_event objects.

This allows queueing to be used by a subsequent change to delay the
virtual mode handling of machine checks that occur in kernel space
where it is unsafe to switch immediately to virtual mode, similarly
to powernv.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fix implicit fallthrough warnings in mce_handle_error()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190802105709.27696-10-npiggin@gmail.com
2019-08-30 10:32:35 +10:00
Nicholas Piggin
7290f3b3d3 powerpc/64s/powernv: machine check dump SLB contents
Re-use the code introduced in pseries to save and dump the contents
of the SLB in the case of an SLB involved machine check exception.

This patch also avoids allocating the SLB save array on pseries radix.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190802105709.27696-9-npiggin@gmail.com
2019-08-30 10:32:35 +10:00
Balbir Singh
895e3dceeb powerpc/mce: Handle UE event for memcpy_mcsafe
If we take a UE on one of the instructions with a fixup entry, set nip
to continue execution at the fixup entry. Stop processing the event
further or print it.

Co-developed-by: Reza Arbab <arbab@linux.ibm.com>
Signed-off-by: Reza Arbab <arbab@linux.ibm.com>
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820081352.8641-6-santosh@fossix.org
2019-08-21 22:23:48 +10:00
Reza Arbab
1a1715f516 powerpc/mce: Make machine_check_ue_event() static
The function doesn't get used outside this file, so make it static.

Signed-off-by: Reza Arbab <arbab@linux.ibm.com>
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820081352.8641-4-santosh@fossix.org
2019-08-21 22:23:47 +10:00
Santosh Sivaraj
b5bda6263c powerpc/mce: Schedule work from irq_work
schedule_work() cannot be called from MCE exception context as MCE can
interrupt even in interrupt disabled context.

Fixes: 733e4a4c44 ("powerpc/mce: hookup memory_failure for UE errors")
Cc: stable@vger.kernel.org # v4.15+
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820081352.8641-2-santosh@fossix.org
2019-08-21 22:23:03 +10:00
Thomas Gleixner
1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Mahesh Salgaonkar
50dbabe06a powerpc/powernv/mce: Print additional information about MCE error.
Print more information about MCE error whether it is an hardware or
software error.

Some of the MCE errors can be easily categorized as hardware or
software errors e.g. UEs are due to hardware error, where as error
triggered due to invalid usage of tlbie is a pure software bug. But
not all the MCE errors can be easily categorize into either software
or hardware. There are errors like multihit errors which are usually
result of a software bug, but in some rare cases a hardware failure
can cause a multihit error. In past, we have seen case where after
replacing faulty chip, multihit errors stopped occurring. Same with
parity errors, which are usually due to faulty hardware but there are
chances where multihit can also cause an parity error. Such errors are
difficult to determine what really caused it. Hence this patch
classifies MCE errors into following four categorize:

  1. Hardware error:
  	UE and Link timeout failure errors.
  2. Probable hardware error (some chance of software cause)
  	SLB/ERAT/TLB Parity errors.
  3. Software error
  	Invalid tlbie form.
  4. Probable software error (some chance of hardware cause)
  	SLB/ERAT/TLB Multihit errors.

Sample output:

  MCE: CPU80: machine check (Warning) Guest SLB Multihit DAR: 000001001b6e0320 [Recovered]
  MCE: CPU80: PID: 24765 Comm: qemu-system-ppc Guest NIP: [00007fffa309dc60]
  MCE: CPU80: Probable Software error (some chance of hardware cause)

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-01 22:23:20 +10:00
Mahesh Salgaonkar
cda6618d06 powerpc/powernv/mce: Print correct severity for MCE error.
Currently all machine check errors are printed as severe errors which
isn't correct. Print soft errors as warning instead of severe errors.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-01 22:22:51 +10:00
Mahesh Salgaonkar
d6e8a15085 powerpc/powernv/mce: Reduce MCE console logs to lesser lines.
Also add cpu number while displaying MCE log. This will help cleaner
logs when MCE hits on multiple cpus simultaneously.

Before the changes the MCE output was:

  Severe Machine check interrupt [Recovered]
    NIP [d00000000ba80280]: insert_slb_entry.constprop.0+0x278/0x2c0 [mcetest_slb]
    Initiator: CPU
    Error type: SLB [Multihit]
      Effective address: d00000000ba80280

After this patch series changes the MCE output will be:

  MCE: CPU80: machine check (Warning) Host SLB Multihit [Recovered]
  MCE: CPU80: NIP: [d00000000b550280] insert_slb_entry.constprop.0+0x278/0x2c0 [mcetest_slb]
  MCE: CPU80: Probable software error (some chance of hardware cause)

UE in host application:

  MCE: CPU48: machine check (Severe) Host UE Load/Store DAR: 00007fffc6079a80 paddr: 0000000f8e260000 [Not recovered]
  MCE: CPU48: PID: 4584 Comm: find NIP: [0000000010023368]
  MCE: CPU48: Hardware error

and for MCE in Guest:

  MCE: CPU80: machine check (Warning) Guest SLB Multihit DAR: 000001001b6e0320 [Recovered]
  MCE: CPU80: PID: 24765 Comm: qemu-system-ppc Guest NIP: [00007fffa309dc60]
  MCE: CPU80: Probable software error (some chance of hardware cause)

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-01 22:22:24 +10:00
Nicholas Piggin
ccd477028a powerpc/64s: Fix HV NMI vs HV interrupt recoverability test
HV interrupts that use HSRR registers do not enter with MSR[RI] clear,
but their entry code is not recoverable vs NMI, due to shared use of
HSPRG1 as a scratch register to save r13.

This means that a system reset or machine check that hits in HSRR
interrupt entry can cause r13 to be silently corrupted.

Fix this by marking NMIs non-recoverable if they land in HV interrupt
ranges.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-26 23:28:24 +11:00
Paul Mackerras
c057720184 powerpc/64s: Better printing of machine check info for guest MCEs
This adds an "in_guest" parameter to machine_check_print_event_info()
so that we can avoid trying to translate guest NIP values into
symbolic form using the host kernel's symbol table.

Reviewed-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-21 23:16:45 +11:00
Mahesh Salgaonkar
a43c159042 powerpc/pseries: Flush SLB contents on SLB MCE errors.
On pseries, as of today system crashes if we get a machine check
exceptions due to SLB errors. These are soft errors and can be fixed
by flushing the SLBs so the kernel can continue to function instead of
system crash. We do this in real mode before turning on MMU. Otherwise
we would run into nested machine checks. This patch now fetches the
rtas error log in real mode and flushes the SLBs on SLB/ERAT errors.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michal Suchanek <msuchanek@suse.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 21:59:22 +10:00
Linus Torvalds
03f51d4efa powerpc updates for 4.16
Highlights:
 
  - Enable support for memory protection keys aka "pkeys" on Power7/8/9 when
    using the hash table MMU.
 
  - Extend our interrupt soft masking to support masking PMU interrupts as well
    as "normal" interrupts, and then use that to implement local_t for a ~4x
    speedup vs the current atomics-based implementation.
 
  - A new driver "ocxl" for "Open Coherent Accelerator Processor Interface
    (OpenCAPI)" devices.
 
  - Support for new device tree properties on PowerVM to describe hotpluggable
    memory and devices.
 
  - Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 64-bit VDSO.
 
  - Freescale updates from Scott:
      "Contains fixes for CPM GPIO and an FSL PCI erratum workaround, plus a
       minor cleanup patch."
 
 As well as quite a lot of other changes all over the place, and small fixes and
 cleanups as always.
 
 Thanks to:
   Alan Modra, Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andreas
   Schwab, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman
   Khandual, Anton Blanchard, Arnd Bergmann, Balbir Singh, Benjamin
   Herrenschmidt, Bhaktipriya Shridhar, Bryant G. Ly, Cédric Le Goater,
   Christophe Leroy, Christophe Lombard, Cyril Bur, David Gibson, Desnes A. Nunes
   do Rosario, Dmitry Torokhov, Frederic Barrat, Geert Uytterhoeven, Guilherme G.
   Piccoli, Gustavo A. R. Silva, Gustavo Romero, Ivan Mikhaylov, Joakim
   Tjernlund, Joe Perches, Josh Poimboeuf, Juan J. Alvarez, Julia Cartwright,
   Kamalesh Babulal, Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre,
   Michael Bringmann, Michael Hanselmann, Michael Neuling, Nathan Fontenot,
   Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Philippe Bergheaud, Ram Pai,
   Russell Currey, Santosh Sivaraj, Scott Wood, Seth Forshee, Simon Guo, Stewart
   Smith, Sukadev Bhattiprolu, Thiago Jung Bauermann, Vaibhav Jain, Vasyl
   Gomonovych.
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Merge tag 'powerpc-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights:

   - Enable support for memory protection keys aka "pkeys" on Power7/8/9
     when using the hash table MMU.

   - Extend our interrupt soft masking to support masking PMU interrupts
     as well as "normal" interrupts, and then use that to implement
     local_t for a ~4x speedup vs the current atomics-based
     implementation.

   - A new driver "ocxl" for "Open Coherent Accelerator Processor
     Interface (OpenCAPI)" devices.

   - Support for new device tree properties on PowerVM to describe
     hotpluggable memory and devices.

   - Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 64-bit
     VDSO.

   - Freescale updates from Scott: fixes for CPM GPIO and an FSL PCI
     erratum workaround, plus a minor cleanup patch.

  As well as quite a lot of other changes all over the place, and small
  fixes and cleanups as always.

  Thanks to: Alan Modra, Alastair D'Silva, Alexey Kardashevskiy,
  Alistair Popple, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V,
  Anju T Sudhakar, Anshuman Khandual, Anton Blanchard, Arnd Bergmann,
  Balbir Singh, Benjamin Herrenschmidt, Bhaktipriya Shridhar, Bryant G.
  Ly, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Cyril Bur,
  David Gibson, Desnes A. Nunes do Rosario, Dmitry Torokhov, Frederic
  Barrat, Geert Uytterhoeven, Guilherme G. Piccoli, Gustavo A. R. Silva,
  Gustavo Romero, Ivan Mikhaylov, Joakim Tjernlund, Joe Perches, Josh
  Poimboeuf, Juan J. Alvarez, Julia Cartwright, Kamalesh Babulal,
  Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre, Michael
  Bringmann, Michael Hanselmann, Michael Neuling, Nathan Fontenot,
  Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Philippe Bergheaud,
  Ram Pai, Russell Currey, Santosh Sivaraj, Scott Wood, Seth Forshee,
  Simon Guo, Stewart Smith, Sukadev Bhattiprolu, Thiago Jung Bauermann,
  Vaibhav Jain, Vasyl Gomonovych"

* tag 'powerpc-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (199 commits)
  powerpc/mm/radix: Fix build error when RADIX_MMU=n
  macintosh/ams-input: Use true and false for boolean values
  macintosh: change some data types from int to bool
  powerpc/watchdog: Print the NIP in soft_nmi_interrupt()
  powerpc/watchdog: regs can't be null in soft_nmi_interrupt()
  powerpc/watchdog: Tweak watchdog printks
  powerpc/cell: Remove axonram driver
  rtc-opal: Fix handling of firmware error codes, prevent busy loops
  powerpc/mpc52xx_gpt: make use of raw_spinlock variants
  macintosh/adb: Properly mark continued kernel messages
  powerpc/pseries: Fix cpu hotplug crash with memoryless nodes
  powerpc/numa: Ensure nodes initialized for hotplug
  powerpc/numa: Use ibm,max-associativity-domains to discover possible nodes
  powerpc/kernel: Block interrupts when updating TIDR
  powerpc/powernv/idoa: Remove unnecessary pcidev from pci_dn
  powerpc/mm/nohash: do not flush the entire mm when range is a single page
  powerpc/pseries: Add Initialization of VF Bars
  powerpc/pseries/pci: Associate PEs to VFs in configure SR-IOV
  powerpc/eeh: Add EEH notify resume sysfs
  powerpc/eeh: Add EEH operations to notify resume
  ...
2018-02-02 10:01:04 -08:00
Linus Torvalds
d4173023e6 Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull siginfo cleanups from Eric Biederman:
 "Long ago when 2.4 was just a testing release copy_siginfo_to_user was
  made to copy individual fields to userspace, possibly for efficiency
  and to ensure initialized values were not copied to userspace.

  Unfortunately the design was complex, it's assumptions unstated, and
  humans are fallible and so while it worked much of the time that
  design failed to ensure unitialized memory is not copied to userspace.

  This set of changes is part of a new design to clean up siginfo and
  simplify things, and hopefully make the siginfo handling robust enough
  that a simple inspection of the code can be made to ensure we don't
  copy any unitializied fields to userspace.

  The design is to unify struct siginfo and struct compat_siginfo into a
  single definition that is shared between all architectures so that
  anyone adding to the set of information shared with struct siginfo can
  see the whole picture. Hopefully ensuring all future si_code
  assignments are arch independent.

  The design is to unify copy_siginfo_to_user32 and
  copy_siginfo_from_user32 so that those function are complete and cope
  with all of the different cases documented in signinfo_layout. I don't
  think there was a single implementation of either of those functions
  that was complete and correct before my changes unified them.

  The design is to introduce a series of helpers including
  force_siginfo_fault that take the values that are needed in struct
  siginfo and build the siginfo structure for their callers. Ensuring
  struct siginfo is built correctly.

  The remaining work for 4.17 (unless someone thinks it is post -rc1
  material) is to push usage of those helpers down into the
  architectures so that architecture specific code will not need to deal
  with the fiddly work of intializing struct siginfo, and then when
  struct siginfo is guaranteed to be fully initialized change copy
  siginfo_to_user into a simple wrapper around copy_to_user.

  Further there is work in progress on the issues that have been
  documented requires arch specific knowledge to sort out.

  The changes below fix or at least document all of the issues that have
  been found with siginfo generation. Then proceed to unify struct
  siginfo the 32 bit helpers that copy siginfo to and from userspace,
  and generally clean up anything that is not arch specific with regards
  to siginfo generation.

  It is a lot but with the unification you can of siginfo you can
  already see the code reduction in the kernel"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (45 commits)
  signal/memory-failure: Use force_sig_mceerr and send_sig_mceerr
  mm/memory_failure: Remove unused trapno from memory_failure
  signal/ptrace: Add force_sig_ptrace_errno_trap and use it where needed
  signal/powerpc: Remove unnecessary signal_code parameter of do_send_trap
  signal: Helpers for faults with specialized siginfo layouts
  signal: Add send_sig_fault and force_sig_fault
  signal: Replace memset(info,...) with clear_siginfo for clarity
  signal: Don't use structure initializers for struct siginfo
  signal/arm64: Better isolate the COMPAT_TASK portion of ptrace_hbptriggered
  ptrace: Use copy_siginfo in setsiginfo and getsiginfo
  signal: Unify and correct copy_siginfo_to_user32
  signal: Remove the code to clear siginfo before calling copy_siginfo_from_user32
  signal: Unify and correct copy_siginfo_from_user32
  signal/blackfin: Remove pointless UID16_SIGINFO_COMPAT_NEEDED
  signal/blackfin: Move the blackfin specific si_codes to asm-generic/siginfo.h
  signal/tile: Move the tile specific si_codes to asm-generic/siginfo.h
  signal/frv: Move the frv specific si_codes to asm-generic/siginfo.h
  signal/ia64: Move the ia64 specific si_codes to asm-generic/siginfo.h
  signal/powerpc: Remove redefinition of NSIGTRAP on powerpc
  signal: Move addr_lsb into the _sigfault union for clarity
  ...
2018-01-30 14:18:52 -08:00
Paul Mackerras
d075745d89 KVM: PPC: Book3S HV: Improve handling of debug-trigger HMIs on POWER9
Hypervisor maintenance interrupts (HMIs) are generated by various
causes, signalled by bits in the hypervisor maintenance exception
register (HMER).  In most cases calling OPAL to handle the interrupt
is the correct thing to do, but the "debug trigger" HMIs signalled by
PPC bit 17 (bit 46) of HMER are used to invoke software workarounds
for hardware bugs, and OPAL does not have any code to handle this
cause.  The debug trigger HMI is used in POWER9 DD2.0 and DD2.1 chips
to work around a hardware bug in executing vector load instructions to
cache inhibited memory.  In POWER9 DD2.2 chips, it is generated when
conditions are detected relating to threads being in TM (transactional
memory) suspended mode when the core SMT configuration needs to be
reconfigured.

The kernel currently has code to detect the vector CI load condition,
but only when the HMI occurs in the host, not when it occurs in a
guest.  If a HMI occurs in the guest, it is always passed to OPAL, and
then we always re-sync the timebase, because the HMI cause might have
been a timebase error, for which OPAL would re-sync the timebase, thus
removing the timebase offset which KVM applied for the guest.  Since
we don't know what OPAL did, we don't know whether to subtract the
timebase offset from the timebase, so instead we re-sync the timebase.

This adds code to determine explicitly what the cause of a debug
trigger HMI will be.  This is based on a new device-tree property
under the CPU nodes called ibm,hmi-special-triggers, if it is
present, or otherwise based on the PVR (processor version register).
The handling of debug trigger HMIs is pulled out into a separate
function which can be called from the KVM guest exit code.  If this
function handles and clears the HMI, and no other HMI causes remain,
then we skip calling OPAL and we proceed to subtract the guest
timebase offset from the timebase.

The overall handling for HMIs that occur in the host (i.e. not in a
KVM guest) is largely unchanged, except that we now don't set the flag
for the vector CI load workaround on DD2.2 processors.

This also removes a BUG_ON in the KVM code.  BUG_ON is generally not
useful in KVM guest entry/exit code since it is difficult to handle
the resulting trap gracefully.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 15:31:25 +11:00
Balbir Singh
733e4a4c44 powerpc/mce: hookup memory_failure for UE errors
If we are in user space and hit a UE error, we now have the
basic infrastructure to walk the page tables and find out
the effective address that was accessed, since the DAR
is not valid.

We use a work_queue content to hookup the bad pfn, any
other context causes problems, since memory_failure itself
can call into schedule() via lru_drain_ bits.

We could probably poison the struct page to avoid a race
between detection and taking corrective action.

Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-16 23:12:02 +11:00
Balbir Singh
ba41e1e1cc powerpc/mce: Hookup derror (load/store) UE errors
Extract physical_address for UE errors by walking the page
tables for the mm and address at the NIP, to extract the
instruction. Then use the instruction to find the effective
address via analyse_instr().

We might have page table walking races, but we expect them to
be rare, the physical address extraction is best effort. The idea
is to then hook up this infrastructure to memory failure eventually.

Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-16 23:12:01 +11:00
Balbir Singh
81b61fa7a0 powerpc/mce: Align the print of physical address better
Use the same alignment as Effective address.

Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-16 23:11:50 +11:00
Balbir Singh
73e341eb6b powerpc/mce: Remove unused function get_mce_fault_addr()
There are no users of get_mce_fault_addr() since commit
1363875bdb ("powerpc/64s: fix handling of non-synchronous machine
checks") removed the last usage.

Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-16 23:11:19 +11:00
Michael Neuling
5080332c2c powerpc/64s: Add workaround for P9 vector CI load issue
POWER9 DD2.1 and earlier has an issue where some cache inhibited
vector load will return bad data. The workaround is two part, one
firmware/microcode part triggers HMI interrupts when hitting such
loads, the other part is this patch which then emulates the
instructions in Linux.

The affected instructions are limited to lxvd2x, lxvw4x, lxvb16x and
lxvh8x.

When an instruction triggers the HMI, all threads in the core will be
sent to the HMI handler, not just the one running the vector load.

In general, these spurious HMIs are detected by the emulation code and
we just return back to the running process. Unfortunately, if a
spurious interrupt occurs on a vector load that's to normal memory we
have no way to detect that it's spurious (unless we walk the page
tables, which is very expensive). In this case we emulate the load but
we need do so using a vector load itself to ensure 128bit atomicity is
preserved.

Some additional debugfs emulated instruction counters are added also.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Switch CONFIG_PPC_BOOK3S_64 to CONFIG_VSX to unbreak the build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-27 08:23:22 +10:00
Michael Ellerman
ccd3cd3613 powerpc/mce: Move 64-bit machine check code into mce.c
We already have mce.c which is built for 64bit and contains other parts
of the machine check code, so move these bits in there too.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 23:31:31 +10:00
Linus Torvalds
d691b7e7d1 powerpc updates for 4.13
Highlights include:
 
  - Support for STRICT_KERNEL_RWX on 64-bit server CPUs.
 
  - Platform support for FSP2 (476fpe) board
 
  - Enable ZONE_DEVICE on 64-bit server CPUs.
 
  - Generic & powerpc spin loop primitives to optimise busy waiting
 
  - Convert VDSO update function to use new update_vsyscall() interface
 
  - Optimisations to hypercall/syscall/context-switch paths
 
  - Improvements to the CPU idle code on Power8 and Power9.
 
 As well as many other fixes and improvements.
 
 Thanks to:
   Akshay Adiga, Andrew Donnellan, Andrew Jeffery, Anshuman Khandual, Anton
   Blanchard, Balbir Singh, Benjamin Herrenschmidt, Christophe Leroy, Christophe
   Lombard, Colin Ian King, Dan Carpenter, Gautham R. Shenoy, Hari Bathini, Ian
   Munsie, Ivan Mikhaylov, Javier Martinez Canillas, Madhavan Srinivasan,
   Masahiro Yamada, Matt Brown, Michael Neuling, Michal Suchanek, Murilo
   Opsfelder Araujo, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Paul
   Mackerras, Pavel Machek, Russell Currey, Santosh Sivaraj, Stephen Rothwell,
   Thiago Jung Bauermann, Yang Li.
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Merge tag 'powerpc-4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights include:

   - Support for STRICT_KERNEL_RWX on 64-bit server CPUs.

   - Platform support for FSP2 (476fpe) board

   - Enable ZONE_DEVICE on 64-bit server CPUs.

   - Generic & powerpc spin loop primitives to optimise busy waiting

   - Convert VDSO update function to use new update_vsyscall() interface

   - Optimisations to hypercall/syscall/context-switch paths

   - Improvements to the CPU idle code on Power8 and Power9.

  As well as many other fixes and improvements.

  Thanks to: Akshay Adiga, Andrew Donnellan, Andrew Jeffery, Anshuman
  Khandual, Anton Blanchard, Balbir Singh, Benjamin Herrenschmidt,
  Christophe Leroy, Christophe Lombard, Colin Ian King, Dan Carpenter,
  Gautham R. Shenoy, Hari Bathini, Ian Munsie, Ivan Mikhaylov, Javier
  Martinez Canillas, Madhavan Srinivasan, Masahiro Yamada, Matt Brown,
  Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Naveen N.
  Rao, Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pavel Machek,
  Russell Currey, Santosh Sivaraj, Stephen Rothwell, Thiago Jung
  Bauermann, Yang Li"

* tag 'powerpc-4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits)
  powerpc/Kconfig: Enable STRICT_KERNEL_RWX for some configs
  powerpc/mm/radix: Implement STRICT_RWX/mark_rodata_ro() for Radix
  powerpc/mm/hash: Implement mark_rodata_ro() for hash
  powerpc/vmlinux.lds: Align __init_begin to 16M
  powerpc/lib/code-patching: Use alternate map for patch_instruction()
  powerpc/xmon: Add patch_instruction() support for xmon
  powerpc/kprobes/optprobes: Use patch_instruction()
  powerpc/kprobes: Move kprobes over to patch_instruction()
  powerpc/mm/radix: Fix execute permissions for interrupt_vectors
  powerpc/pseries: Fix passing of pp0 in updatepp() and updateboltedpp()
  powerpc/64s: Blacklist rtas entry/exit from kprobes
  powerpc/64s: Blacklist functions invoked on a trap
  powerpc/64s: Un-blacklist system_call() from kprobes
  powerpc/64s: Move system_call() symbol to just after setting MSR_EE
  powerpc/64s: Blacklist system_call() and system_call_common() from kprobes
  powerpc/64s: Convert .L__replay_interrupt_return to a local label
  powerpc64/elfv1: Only dereference function descriptor for non-text symbols
  cxl: Export library to support IBM XSL
  powerpc/dts: Use #include "..." to include local DT
  powerpc/perf/hv-24x7: Aggregate result elements on POWER9 SMT8
  ...
2017-07-07 13:55:45 -07:00
Mahesh Salgaonkar
8aa586c688 powerpc/book3s: EXPORT_SYMBOL_GPL machine_check_print_event_info
It will be used in arch/powerpc/kvm/book3s_hv.c KVM module.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-06-21 13:52:05 +10:00
Nicholas Piggin
90df4bfb4d powerpc/64s: Machine check handle ifetch from foreign real address for POWER9
The i-side 0111b machine check, which is "Instruction Fetch to foreign
address space", was missed by 7b9f71f974 ("powerpc/64s: POWER9 machine
check handler").

    The POWER9 processor core considers host real addresses with a
    nonzero value in RA(8:12) as foreign address space, accessible only
    by the copy and paste instructions. The copy and paste instruction
    pair can be used to invoke the Nest accelerators via the Virtual
    Accelerator Switchboard (VAS).

It is an error for any regular load/store or ifetch to go to a foreign
addresses. When relocation is on, this causes an MMU exception. When
relocation is off, a machine check exception. It is possible to trigger
this machine check by branching to a foreign address with MSR[IR]=0.

Fixes: 7b9f71f974 ("powerpc/64s: POWER9 machine check handler")
Reported-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-06 21:17:15 +10:00
Mahesh Salgaonkar
d93b0ac01a powerpc/book3s/mce: Move add_taint() later in virtual mode
machine_check_early() gets called in real mode. The very first time when
add_taint() is called, it prints a warning which ends up calling opal
call (that uses OPAL_CALL wrapper) for writing it to console. If we get a
very first machine check while we are in opal we are doomed. OPAL_CALL
overwrites the PACASAVEDMSR in r13 and in this case when we are done with
MCE handling the original opal call will use this new MSR on it's way
back to opal_return. This usually leads to unexpected behaviour or the
kernel to panic. Instead move the add_taint() call later in the virtual
mode where it is safe to call.

This is broken with current FW level. We got lucky so far for not getting
very first MCE hit while in OPAL. But easily reproducible on Mambo.

Fixes: 27ea2c420c ("powerpc: Set the correct kernel taint on machine check errors.")
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-03 14:45:39 +10:00
Michael Ellerman
63f44d6514 powerpc/book3s: Print task info if we take a machine check in user mode
For an MCE (Machine Check Exception) that hits while in user mode
MSR(PR=1), print the task info to the console MCE error log. This may
help to identify an application that triggered the MCE.

After this patch the MCE console looks like:

  Severe Machine check interrupt [Recovered]
    NIP: [0000000010039778] PID: 762 Comm: ebizzy
    Initiator: CPU
    Error type: SLB [Multihit]
      Effective address: 0000000010039778

  Severe Machine check interrupt [Not recovered]
    NIP: [0000000010039778] PID: 763 Comm: ebizzy
    Initiator: CPU
    Error type: UE [Page table walk ifetch]
      Effective address: 0000000010039778
  ebizzy[763]: unhandled signal 7 at 0000000010039778 nip 0000000010039778 lr 0000000010001b44 code 30004

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-03 16:12:00 +10:00
Mahesh Salgaonkar
5b1d6fc2d4 powerpc/book3s: Print the kernel function name in machine check
For D-side errors we print the load/store address that caused the
machine check as 'Effective address'. But the instruction that may have
caused the machine check can also be helpful, so in addition to printing
the NIP, also print the kernel function name as well.

After this patch the MCE console log would look like:

  Severe Machine check interrupt [Recovered]
    NIP [d00000001bc70194]: init_module+0x194/0x2b0 [bork_kernel]
    Initiator: CPU
    Error type: SLB [Parity]
      Effective address: d000000026de0000

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-03 16:11:36 +10:00
Nicholas Piggin
fc84427b7e powerpc/64s: Machine check print NIP
Print the faulting address of the machine check that may help with
debugging. The effective address reported can be a target memory address
rather than the faulting instruction address.

Fix up a dangling bracket while here.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-21 22:09:28 +11:00
Nicholas Piggin
7b9f71f974 powerpc/64s: POWER9 machine check handler
Add POWER9 machine check handler. There are several new types of errors
added, so logging messages for those are also added.

This doesn't attempt to reuse any of the P7/8 defines or functions,
because that becomes too complex. The better option in future is to use
a table driven approach.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-10 16:32:08 +11:00
Nicholas Piggin
c1bbf387d6 powerpc/64s: allow machine check handler to set severity and initiator
Currently severity and initiator are always set to MCE_SEV_ERROR_SYNC and
MCE_INITIATOR_CPU in the core mce code. Allow them to be set by the
machine specific mce handlers.

No functional change for existing handlers.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-10 16:32:07 +11:00
Tobias Klauser
d6d56ec738 powerpc/mce: Remove unused but set variable
Remove the unused but set variable srr1 in save_mce_event() to
fix the following GCC warning when building with 'W=1':

  arch/powerpc/kernel/mce.c:75:11: warning: variable 'srr1' set but not used

It has never been used.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-18 22:40:38 +11:00