The function should return NULL in case no device is found, but it
always returns the last checked mc device from the list even if the
index did not match. Fix that.

I did some analysis why this did not raise any issues for about 3 years
and the reason is that edac_mc_find() is mostly used to search for
existing devices. Thus, the bug is not triggered.

 [ bp: Drop the if (mci->mc_idx > idx) test in favor of readability. ]

Fixes: c73e8833 ("EDAC, mc: Fix locking around mc_devices list")
Signed-off-by: NRobert Richter <rrichter@marvell.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: "linux-edac@vger.kernel.org" <linux-edac@vger.kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lkml.kernel.org/r/20190514104838.15065-1-rrichter@marvell.com

... and use the single edac_subsys object returned from
subsys_system_register(). The idea is to have a single bus
and multiple devices on it.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>
CC: Aristeu Rozanski Filho <arozansk@redhat.com>
CC: Greg KH <gregkh@linuxfoundation.org>
CC: Justin Ernst <justin.ernst@hpe.com>
CC: linux-edac <linux-edac@vger.kernel.org>
CC: Mauro Carvalho Chehab <mchehab@kernel.org>
CC: Russ Anderson <rja@hpe.com>
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20180926152752.GG5584@zn.tnic

The edac_mem_types[] array misses a MEM_LRDDR4 entry, which leads to
NULL pointer dereference when accessed via sysfs or such.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Yazen Ghannam <Yazen.Ghannam@amd.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20180810141426.8918-1-tiwai@suse.de
Fixes: 1e8096bb ("EDAC: Add LRDDR4 DRAM type")
Signed-off-by: NBorislav Petkov <bp@suse.de>

There are now non-volatile versions of DIMMs. Add a new entry to "enum
mem_type" and a new string in edac_mem_types[].
Signed-off-by: NTony Luck <tony.luck@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Aristeu Rozanski <aris@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Cc: linux-acpi@vger.kernel.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/20180312182430.10335-3-tony.luck@intel.comSigned-off-by: NBorislav Petkov <bp@suse.de>

Somehow we ended up with two separate arrays of strings to describe the
"enum mem_type" values.

In edac_mc.c we have an exported list edac_mem_types[] that is used
by a couple of drivers in debug messaged.

In edac_mc_sysfs.c we have a private list that is used to display
values in:
  /sys/devices/system/edac/mc/mc*/dimm*/dimm_mem_type
  /sys/devices/system/edac/mc/mc*/csrow*/mem_type

This list was missing a value for MEM_LRDDR3.

The string values in the two lists were different :-(

Combining the lists, I kept the values so that the sysfs output
will be unchanged as some scripts may depend on that.
Reported-by: NBorislav Petkov <bp@suse.de>
Acked-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NTony Luck <tony.luck@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Aristeu Rozanski <aris@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Cc: linux-acpi@vger.kernel.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/20180312182430.10335-2-tony.luck@intel.comSigned-off-by: NBorislav Petkov <bp@suse.de>

Only a single EDAC platform driver can be loaded. When ghes_edac is
enabled, an EDAC platform driver still attempts to register itself and
fails in edac_mc_add_mc().

Add edac_get_owner() so that EDAC platform drivers can check the owner
first.
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Suggested-by: NBorislav Petkov <bp@alien8.de>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170823225447.15608-5-toshi.kani@hpe.com
[ Massage commit message. ]
Signed-off-by: NBorislav Petkov <bp@suse.de>

Change them to have the edac_ prefix.

No functionality change.
Signed-off-by: NBorislav Petkov <bp@suse.de>

Move the remaining functionality to edac_mc.c. Convert "edac_report=" to
a module parameter.
Signed-off-by: NBorislav Petkov <bp@suse.de>

... and this happens only when CONFIG_RAS is enabled.
Signed-off-by: NBorislav Petkov <bp@suse.de>

... as part of moving stuff away from edac_stub.c
Signed-off-by: NBorislav Petkov <bp@suse.de>

... and the glue around it. It is not needed anymore.
Signed-off-by: NBorislav Petkov <bp@suse.de>

Use mc_devices list instead to check whether we have EDAC driver
instances successfully registered with EDAC core.
Signed-off-by: NBorislav Petkov <bp@suse.de>

We need to know if any MC devices have been allocated.
Signed-off-by: NYazen Ghannam <Yazen.Ghannam@amd.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1485537863-2707-7-git-send-email-Yazen.Ghannam@amd.com
[ Prettify text. ]
Signed-off-by: NBorislav Petkov <bp@suse.de>

This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.
Requested-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Several functions are documented at edac_mc.c.

As we'll be including edac_core.h at drivers-api book, move
those, in order for the kernel-doc markups be part of the API
documentation book.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Now, all left at edac_core.h are at drivers/edac/edac_mc.c,
so rename it to edac_mc.h.
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

When accessing the mc_devices list of memory controller descriptors, we
need to hold mem_ctls_mutex. This was not always the case, fix that.

Make all external callers call a version which grabs the mutex since the
last is local to edac_mc.c.
Reported-by: NYazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>

After the workqueue cleanup, we're registering workqueues based on
the presence of an ->edac_check function. When that is the case,
we're setting OP_RUNNING_POLL. But we forgot to check that in
edac_mc_reset_delay_period(), leading to:

  BUG: unable to handle kernel paging request at 0000000000015d10
  IP: [ .. ] queued_spin_lock_slowpath
  PGD 3ffcc8067 PUD 3ffc56067 PMD 0
  Oops: 0002 [#1] SMP
  Modules linked in: ...
  CPU: 1 PID: 2792 Comm: edactest Not tainted 4.6.0-dirty #1
  Hardware name: HP ProLiant MicroServer, BIOS O41     10/01/2013
  Stack:
  Call Trace:
    ? _raw_spin_lock_irqsave
    ? lock_timer_base.isra.34
    ? del_timer
    ? try_to_grab_pending
    ? mod_delayed_work_on
    ? edac_mc_reset_delay_period
    ? edac_set_poll_msec
    ? param_attr_store
    ? module_attr_store
    ? kernfs_fop_write
    ? __vfs_write
    ? __vfs_read
    ? __alloc_fd
    ? vfs_write
    ? SyS_write
    ? entry_SYSCALL_64_fastpath
  Code:
  RIP  [ .. ] queued_spin_lock_slowpath
   RSP <>
  CR2: 0000000000015d10
  ---[ end trace 3f286bc71cca15d1 ]---
  Kernel panic - not syncing: Fatal exception

Fix it.
Signed-off-by: NNicholas Krause <xerofoify@gmail.com>
Cc: <stable@vger.kernel.org> # 4.5
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1463697958-13406-1-git-send-email-xerofoify@gmail.com
[ Rewrite commit message. ]
Signed-off-by: NBorislav Petkov <bp@suse.de>

Fix typo in edac_inc_ue_error() to increment ue_noinfo_count instead of
ce_noinfo_count.
Signed-off-by: NEmmanouil Maroudas <emmanouil.maroudas@gmail.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Fixes: 4275be63 ("edac: Change internal representation to work with layers")
Link: http://lkml.kernel.org/r/1461425580-5898-1-git-send-email-emmanouil.maroudas@gmail.comSigned-off-by: NBorislav Petkov <bp@suse.de>

They're both running only when ->edac_check is initialized so remove
that check from the workqueue function itself. Synchronize/generalize
the ->op_state check between the two.

Kill useless comments, while at it.
Signed-off-by: NBorislav Petkov <bp@suse.de>

We have the generic wrappers now, use those. edac_pci_workq_setup() had
an unused argument anyway.
Signed-off-by: NBorislav Petkov <bp@suse.de>

We use the ->edac_check function pointers to determine whether we need
to setup a polling workqueue. However, the destroy path is not balanced
and we might try to teardown an unitialized workqueue.

Balance init and destroy paths by looking at ->edac_check in both cases.
Set op_state to OP_OFFLINE *before* destroying anything.
Reported-by: NZhiqiang Hou <Zhiqiang.Hou@freescale.com>
Cc: Varun Sethi <Varun.Sethi@freescale.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>

Hide the EDAC workqueue pointer in a separate compilation unit and add
accessors for the workqueue manipulations needed.

Remove edac_pci_reset_delay_period() which wasn't used by anything. It
seems it got added without a user with

  91b99041 ("drivers/edac: updated PCI monitoring")
Signed-off-by: NBorislav Petkov <bp@suse.de>

EDAC workqueue destruction is really fragile. We cancel delayed work
but if it is still running and requeues itself, we still go ahead and
destroy the workqueue and the queued work explodes when workqueue core
attempts to run it.

Make the destruction more robust by switching op_state to offline so
that requeuing stops. Cancel any pending work *synchronously* too.

  EDAC i7core: Driver loaded.
  general protection fault: 0000 [#1] SMP
  CPU 12
  Modules linked in:
  Supported: Yes
  Pid: 0, comm: kworker/0:1 Tainted: G          IE   3.0.101-0-default #1 HP ProLiant DL380 G7
  RIP: 0010:[<ffffffff8107dcd7>]  [<ffffffff8107dcd7>] __queue_work+0x17/0x3f0
  < ... regs ...>
  Process kworker/0:1 (pid: 0, threadinfo ffff88019def6000, task ffff88019def4600)
  Stack:
   ...
  Call Trace:
   call_timer_fn
   run_timer_softirq
   __do_softirq
   call_softirq
   do_softirq
   irq_exit
   smp_apic_timer_interrupt
   apic_timer_interrupt
   intel_idle
   cpuidle_idle_call
   cpu_idle
  Code: ...
  RIP  __queue_work
   RSP <...>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>

The PAGES_TO_MiB macro is used for unit conversion but the
trace_mc_event() tracepoint expects a page address. Fix that.
Signed-off-by: NTan Xiaojun <tanxiaojun@huawei.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1445341538-24271-1-git-send-email-tanxiaojun@huawei.comSigned-off-by: NBorislav Petkov <bp@suse.de>

So first of all, this atomic_scrub() function's naming is bad. It looks
like an atomic_t helper. Change it to edac_atomic_scrub().

The bigger problem is that this function is arch-specific and every new
arch which doesn't necessarily need that functionality still needs to
define it, otherwise EDAC doesn't compile.

So instead of doing that and including arch-specific headers, have each
arch define an EDAC_ATOMIC_SCRUB symbol which can be used in edac_mc.c
for ifdeffery. Much cleaner.

And we already are doing this with another symbol - EDAC_SUPPORT. This
is also much cleaner than having CONFIG_EDAC enumerate all the arches
which need/have EDAC support and drivers.

This way I can kill the useless edac.h header in tile too.
Acked-by: NRalf Baechle <ralf@linux-mips.org>
Acked-by: NMichael Ellerman <mpe@ellerman.id.au>
Acked-by: NChris Metcalf <cmetcalf@ezchip.com>
Acked-by: NIngo Molnar <mingo@kernel.org>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Doug Thompson <dougthompson@xmission.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-edac@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: "Maciej W. Rozycki" <macro@codesourcery.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Steven J. Hill" <Steven.Hill@imgtec.com>
Cc: x86@kernel.org
Signed-off-by: NBorislav Petkov <bp@suse.de>

Add edac_mc_add_mc_with_groups() for initializing the mem_ctl_info
object with the optional attribute groups.  This allows drivers to
pass additional sysfs entries without manual (and racy)
device_create_file() and co calls.

edac_mc_add_mc() is kept as is, just calling edac_mc_add_with_groups()
with NULL groups.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Link: http://lkml.kernel.org/r/1423046938-18111-3-git-send-email-tiwai@suse.deSigned-off-by: NBorislav Petkov <bp@suse.de>

Make keeping the sync between the mem_types enum and the actual string
names simpler by using designated initializers.
Signed-off-by: NBorislav Petkov <bp@suse.de>

F15hM60h adds support for DDR4 and DDR3 LRDIMMs. Add them here.
Signed-off-by: NAravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Link: http://lkml.kernel.org/r/1411070218-10258-1-git-send-email-Aravind.Gopalakrishnan@amd.com
[ Boris: improve comments. ]
Signed-off-by: NBorislav Petkov <bp@suse.de>

This one got forgotten during an earlier cleanup.
Signed-off-by: NBorislav Petkov <bp@suse.de>

To avoid confuision and conflict of usage for RAS related trace event,
add an unified RAS trace event stub.

Start a RAS subsystem menu which will be fleshed out in time, when more
features get added to it.
Signed-off-by: NChen, Gong <gong.chen@linux.intel.com>
Link: http://lkml.kernel.org/r/1402475691-30045-2-git-send-email-gong.chen@linux.intel.comSigned-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NTony Luck <tony.luck@intel.com>

The MC structure field scrub_mode is of integer type - not bit field.
Use it accordingly.
Signed-off-by: NLoc Ho <lho@apm.com>
Link: http://lkml.kernel.org/r/1399590199-12256-2-git-send-email-lho@apm.comSigned-off-by: NBorislav Petkov <bp@suse.de>

We're using edac_mc_workq_setup() both on the init path, when
we load an edac driver and when we change the polling period
(edac_mc_reset_delay_period) through /sys/.../edac_mc_poll_msec.

On that second path we don't need to init the workqueue which has been
initialized already.

Thanks to Tejun for workqueue insights.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1391457913-881-1-git-send-email-prarit@redhat.com
Cc: <stable@vger.kernel.org>

Sanitize code even more to accept unsigned longs only and to not allow
polling intervals below 1 second as this is unnecessary and doesn't make
much sense anyway for polling errors.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1391457913-881-1-git-send-email-prarit@redhat.com
Cc: Doug Thompson <dougthompson@xmission.com>
Cc: <stable@vger.kernel.org>

Log messages slightly differ between edac subsystems. Unifying it.
Signed-off-by: NRobert Richter <robert.richter@linaro.org>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NRobert Richter <rric@kernel.org>

Fix the following:

BUG: key ffff88043bdd0330 not in .data!
------------[ cut here ]------------
WARNING: at kernel/lockdep.c:2987 lockdep_init_map+0x565/0x5a0()
DEBUG_LOCKS_WARN_ON(1)
Modules linked in: glue_helper sb_edac(+) edac_core snd acpi_cpufreq lrw gf128mul ablk_helper iTCO_wdt evdev i2c_i801 dcdbas button cryptd pcspkr iTCO_vendor_support usb_common lpc_ich mfd_core soundcore mperf processor microcode
CPU: 2 PID: 599 Comm: modprobe Not tainted 3.10.0 #1
Hardware name: Dell Inc. Precision T3600/0PTTT9, BIOS A08 01/24/2013
 0000000000000009 ffff880439a1d920 ffffffff8160a9a9 ffff880439a1d958
 ffffffff8103d9e0 ffff88043af4a510 ffffffff81a16e11 0000000000000000
 ffff88043bdd0330 0000000000000000 ffff880439a1d9b8 ffffffff8103dacc
Call Trace:
  dump_stack
  warn_slowpath_common
  warn_slowpath_fmt
  lockdep_init_map
  ? trace_hardirqs_on_caller
  ? trace_hardirqs_on
  debug_mutex_init
  __mutex_init
  bus_register
  edac_create_sysfs_mci_device
  edac_mc_add_mc
  sbridge_probe
  pci_device_probe
  driver_probe_device
  __driver_attach
  ? driver_probe_device
  bus_for_each_dev
  driver_attach
  bus_add_driver
  driver_register
  __pci_register_driver
  ? 0xffffffffa0010fff
  sbridge_init
  ? 0xffffffffa0010fff
  do_one_initcall
  load_module
  ? unset_module_init_ro_nx
  SyS_init_module
  tracesys
---[ end trace d24a70b0d3ddf733 ]---
EDAC MC0: Giving out device to 'sbridge_edac.c' 'Sandy Bridge Socket#0': DEV 0000:3f:0e.0
EDAC sbridge: Driver loaded.

What happens is that bus_register needs a statically allocated lock_key
because the last is handed in to lockdep. However, struct mem_ctl_info
embeds struct bus_type (the whole struct, not a pointer to it) and the
whole thing gets dynamically allocated.

Fix this by using a statically allocated struct bus_type for the MC bus.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NMauro Carvalho Chehab <mchehab@infradead.org>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: stable@kernel.org # v3.10
Signed-off-by: NTony Luck <tony.luck@intel.com>

Both mci.mem_is_per_rank and mci.csbased denote the same thing: the
memory controller is csrows based. Merge both fields into one.

There's no need for the driver to actually fill it, as the core detects
it by checking if one of the layers has the csrows type as part of the
memory hierarchy:

	if (layers[i].type == EDAC_MC_LAYER_CHIP_SELECT)
			per_rank = true;
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>

That allows APEI GHES driver to report errors directly, using
the EDAC error report API.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The number of variables at the stack is too big.
Reduces the stack usage by using a pre-allocated error
buffer.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

APEI GHES and i7core_edac/sb_edac currently can be loaded at
the same time, but those are Highlander modules:
	"There can be only one".

There are two reasons for that:

1) Each driver assumes that it is the only one registering at
   the EDAC core, as it is driver's responsibility to number
   the memory controllers, and all of them start from 0;

2) If BIOS is handling the memory errors, the OS can't also be
   doing it, as one will mangle with the other.

So, we need to add an module owner's lock at the EDAC core,
in order to avoid having two different modules handling memory
errors at the same time. The best way for doing this lock seems
to use the driver's name, as this is unique, and won't require
changes on every driver.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>