Some early controllers incorrectly reported zero ports in PORTS_IMPL
register and the ahci driver fabricates PORTS_IMPL from the number of
ports in those cases. This hasn't mattered but with the new nvme
controllers there are cases where zero PORTS_IMPL is valid and should
be honored.
Hash implementations that require a key may crash if you use
them without setting a key. This patch adds the necessary checks
so that if you do attempt to use them without a key that we return
-ENOKEY instead of proceeding.
This patch also adds a compatibility path to support old applications
that do acept(2) before setkey.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Each af_alg parent socket obtained by socket(2) corresponds to a
tfm object once bind(2) has succeeded. An accept(2) call on that
parent socket creates a context which then uses the tfm object.
Therefore as long as any child sockets created by accept(2) exist
the parent socket must not be modified or freed.
This patch guarantees this by using locks and a reference count
on the parent socket. Any attempt to modify the parent socket will
fail with EBUSY.
Some cipher implementations will crash if you try to use them
without calling setkey first. This patch adds a check so that
the accept(2) call will fail with -ENOKEY if setkey hasn't been
done on the socket yet.
c118baf80256 ("arch/powerpc/mm/numa.c: do not allocate bootmem memory for non existing nodes")
avoids allocating bootmem memory for non existent nodes.
But when DEBUG_PER_CPU_MAPS=y is enabled, my powerNV system failed to boot
because in sched_init_numa(), cpumask_or() operation was done on
unallocated nodes.
Fix that by making cpumask_or() operation only on existing nodes.
[ Tested with and w/o DEBUG_PER_CPU_MAPS=y on x86 and PowerPC. ]
When tearing down page tables, we return early for the final level
since we know that we won't have any table pointers to follow.
Unfortunately, this also means that we forget to free the final level,
so we end up leaking memory.
Fix the issue by always freeing the current level, but just don't bother
to iterate over the ptes if we're at the final level.
Reported-by: Zhang Bo <zhangbo_a@xiaomi.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ioctl(TIOCGETD) retrieves the line discipline id directly from the
ldisc because the line discipline id (c_line) in termios is untrustworthy;
userspace may have set termios via ioctl(TCSETS*) without actually
changing the line discipline via ioctl(TIOCSETD).
However, directly accessing the current ldisc via tty->ldisc is
unsafe; the ldisc ptr dereferenced may be stale if the line discipline
is changing via ioctl(TIOCSETD) or hangup.
Wait for the line discipline reference (just like read() or write())
to retrieve the "current" line discipline id.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A small window exists where a tty reopen will observe the tty
just prior to imminent teardown (tty->count == 0); in this case, open()
returns EIO to userspace.
Instead, retry the open after checking for signals and yielding;
this interruptible retry loop allows teardown to commence and initialize
a new tty on retry. Never retry the BSD master pty reopen; there is no
guarantee the pty pair teardown is imminent since the slave file
descriptors may remain open indefinitely.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Although n_tty_check_unthrottle() has a valid ldisc reference (since
the tty core gets the ldisc ref in tty_read() before calling the line
discipline read() method), it does not have a valid ldisc reference to
the "other" pty of a pty pair. Since getting an ldisc reference for
tty->link essentially open-codes tty_wakeup(), just replace with the
equivalent tty_wakeup().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit abce329c27b3 ("xhci: Workaround to get D3 working in Intel xHCI")
adds a workaround for a limitation of PME storm caused by SSIC port in
some Intel SoCs. This commit only handled one SSIC port, while there
are actually two SSIC ports in the chips. This patch handles both SSIC
ports. Without this fix, users still see PME storm.
Signed-off-by: Zhuang Jin Can <jin.can.zhuang@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This driver registers for extcon events as part of its probe, but
never unregisters them in case of error in the probe path.
There were multiple issues noticed due to this missing error handling.
One of them is random crashes if the regulators are not ready yet by the
time probe is invoked.
Ivan's previous attempt [1] to fix this issue, did not really address
all the failure cases like regualtor/get_irq failures.
Fixes: 591fc116f330 ("usb: phy: msm: Use extcon framework for VBUS and ID detection") Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Felipe Balbi <balbi@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For Intel 7260 modem, it is needed for host side to send zero
packet if the BULK OUT size is equal to USB endpoint max packet
length. Otherwise, modem side may still wait for more data and
cannot give response to host side.
Signed-off-by: Konrad Leszczynski <konrad.leszczynski@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In current acm driver, the bulk-in callback function ignores the
URBs unlinked in usb core.
This causes unexpected data loss in some cases. For example,
runtime suspend entry will unlinked all urbs and set urb->status
to -ENOENT even those urbs might have data not processed yet.
Hence, data loss occurs.
This patch lets bulk-in callback function handle unlinked urbs
to avoid data loss.
Signed-off-by: Tang Jian Qiang <jianqiang.tang@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Acked-by: Oliver Neukum <oneukum@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In certain kernel configurations where the cdc_ether and option drivers
are compiled as modules there can occur a race condition in enumeration.
This causes the option driver to enumerate the ethernet(wwan) interface
as usb-serial interfaces.
Signed-off-by: John Ernberg <john.ernberg@actia.se> Fixes: 1941138e1c02 ("USB: added support for Cinterion's products...") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In function usb_reset_and_verify_device, the old BOS descriptor may
still be used before allocating a new one. (usb_unlocked_disable_lpm
function uses it under the situation that it fails to disable lpm.)
So we cannot set the udev->bos to NULL before that, just keep what it
was. It will be overwrite when allocating a new one.
The visor driver crashes in clie_5_attach() when a specially crafted USB
device without bulk-out endpoint is detected. This fix adds a check that
the device has proper configuration expected by the driver.
Currently the selected timer backend is referred at any moment from
the running PCM callbacks. When the backend is switched, it's
possible to lead to inconsistency from the running backend. This was
pointed by syzkaller fuzzer, and the commit [7ee96216c31a: ALSA:
dummy: Disable switching timer backend via sysfs] disabled the dynamic
switching for avoiding the crash.
This patch improves the handling of timer backend switching. It keeps
the reference to the selected backend during the whole operation of an
opened stream so that it won't be changed by other streams.
Together with this change, the hrtimer parameter is reenabled as
writable now.
NOTE: this patch also turned out to fix the still remaining race.
Namely, ops was still replaced dynamically at dummy_pcm_open:
static int dummy_pcm_open(struct snd_pcm_substream *substream)
{
....
dummy->timer_ops = &dummy_systimer_ops;
if (hrtimer)
dummy->timer_ops = &dummy_hrtimer_ops;
Since dummy->timer_ops is common among all streams, and when the
replacement happens during accesses of other streams, it may lead to a
crash. This was actually triggered by syzkaller fuzzer and KASAN.
This patch rewrites the code not to use the ops shared by all streams
any longer, too.
The hda_jack_tbl entries are managed by snd_array for allowing
multiple jacks. It's good per se, but the problem is that struct
hda_jack_callback keeps the hda_jack_tbl pointer. Since snd_array
doesn't preserve each pointer at resizing the array, we can't keep the
original pointer but have to deduce the pointer at each time via
snd_array_entry() instead. Actually, this resulted in the deference
to the wrong pointer on codecs that have many pins such as CS4208.
This patch replaces the pointer to the NID value as the search key.
As an unexpected good side effect, this even simplifies the code, as
only NID is needed in most cases.
The original commit disabled the aamixer path due to the noise
problem, but it turned out that some mobo with the same PCI SSID
doesn't suffer from the issue, and the disabled function (analog
loopback) is still demanded by users.
Since the recent commit [e7fdd52779a6: ALSA: hda - Implement loopback
control switch for Realtek and other codecs], we have the dynamic
mixer switch to enable/disable the aamix path, and we don't have to
disable the path statically any longer. So, let's revert the
disablement, so that only the user suffering from the noise problem
can turn off the aamix on the fly.
sound/pci/hda/patch_hdmi.c:460 hdmi_eld_ctl_get()
error: __memcpy() 'eld->eld_buffer' too small (256 vs 512)
I have a hard time figuring out if this can ever cause an information leak
(I don't think so), but nonetheless it does not hurt to increase the
robustness of the code.
Fixes: 68e03de98507 ('ALSA: hda - hdmi: Do not expose eld data when eld is invalid') Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Henningsson <david.henningsson@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mac Mini 7,1 model with CS4208 codec reports the headphone jack
detection wrongly in an inverted way. Moreover, the advertised pins
for the audio input and SPDIF output have actually no jack detection.
This patch addresses these issues. The inv_jack_detect flag is set
for fixing the headphone jack detection, and the pin configs for audio
input and SPDIF output are marked as non-detectable.
A slave timer element also unlinks at snd_timer_stop() but it takes
only slave_active_lock. When a slave is assigned to a master,
however, this may become a race against the master's interrupt
handling, eventually resulting in a list corruption. The actual bug
could be seen with a syzkaller fuzzer test case in BugLink below.
As a fix, we need to take timeri->timer->lock when timer isn't NULL,
i.e. assigned to a master, while the assignment to a master itself is
protected by slave_active_lock.
In snd_timer_notify1(), the wrong timer instance was passed for slave
ccallback function. This leads to the access to the wrong data when
an incompatible master is handled (e.g. the master is the sequencer
timer and the slave is a user timer), as spotted by syzkaller fuzzer.
snd_timer_user_read() has a potential race among parallel reads, as
qhead and qused are updated outside the critical section due to
copy_to_user() calls. Move them into the critical section, and also
sanitize the relevant code a bit.
Although ALSA timer code got hardening for races, it still causes
use-after-free error. This is however rather a corrupted linked list,
not actually the concurrent accesses. Namely, when timer start is
triggered twice, list_add_tail() is called twice, too. This ends
up with the link corruption and triggers KASAN error.
The simplest fix would be replacing list_add_tail() with
list_move_tail(), but fundamentally it's the problem that we don't
check the double start/stop correctly. So, the right fix here is to
add the proper checks to snd_timer_start() and snd_timer_stop() (and
their variants).
In ALSA timer core, the active timer instance is managed in
active_list linked list. Each element is added / removed dynamically
at timer start, stop and in timer interrupt. The problem is that
snd_timer_interrupt() has a thinko and leaves the element in
active_list when it's the last opened element. This eventually leads
to list corruption or use-after-free error.
This hasn't been revealed because we used to delete the list forcibly
in snd_timer_stop() in the past. However, the recent fix avoids the
double-stop behavior (in commit [f784beb75ce8: ALSA: timer: Fix link
corruption due to double start or stop]), and this leak hits reality.
This patch fixes the link management in snd_timer_interrupt(). Now it
simply unlinks no matter which stream is.
This is a minor code cleanup without any functional changes:
- Kill keep_flag argument from _snd_timer_stop(), as all callers pass
only it false.
- Remove redundant NULL check in _snd_timer_stop().
The port subscription code uses double mutex locks for source and
destination ports, and this may become racy once when wrongly set up.
It leads to lockdep warning splat, typically triggered by fuzzer like
syzkaller, although the actual deadlock hasn't been seen, so far.
This patch simplifies the handling by reducing to two single locks, so
that no lockdep warning will be trigger any longer.
By splitting to two actions, a still-in-progress element shall be
added in one list while handling another. For ignoring this element,
a new check is added in deliver_to_subscribers().
Along with it, the code to add/remove the subscribers list element was
cleaned up and refactored.
ALSA sequencer may open/close and control ALSA timer instance
dynamically either via sequencer events or direct ioctls. These are
done mostly asynchronously, and it may call still some timer action
like snd_timer_start() while another is calling snd_timer_close().
Since the instance gets removed by snd_timer_close(), it may lead to
a use-after-free.
This patch tries to address such a race by protecting each
snd_timer_*() call via the existing spinlock and also by avoiding the
access to timer during close call.
While performing hw_free, DPCM checks the BE state but leaves out
the suspend state. The suspend state needs to be checked as well,
as we might be suspended and then usermode closes rather than
resuming the audio stream.
This was found by a stress testing of system with playback in
loop and killed after few seconds running in background and second
script running suspend-resume test in loop
Signed-off-by: Vinod Koul <vinod.koul@intel.com> Acked-by: Liam Girdwood <liam.r.girdwood@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are potential deadlocks in PCM OSS emulation code while
accessing read/write and mmap concurrently. This comes from the
infamous mmap_sem usage in copy_from/to_user(). Namely,
The rawmidi read and write functions manage runtime stream status
such as runtime->appl_ptr and runtime->avail. These point where to
copy the new data and how many bytes have been copied (or to be
read). The problem is that rawmidi read/write call copy_from_user()
or copy_to_user(), and the runtime spinlock is temporarily unlocked
and relocked while copying user-space. Since the current code
advances and updates the runtime status after the spin unlock/relock,
the copy and the update may be asynchronous, and eventually
runtime->avail might go to a negative value when many concurrent
accesses are done. This may lead to memory corruption in the end.
For fixing this race, in this patch, the status update code is
performed in the same lock before the temporary unlock. Also, the
spinlock is now taken more widely in snd_rawmidi_kernel_read1() for
protecting more properly during the whole operation.
NULL user-space buffer can be passed even in a normal path, thus it's
not good to spew a kernel warning with stack trace at each time.
Just drop snd_BUG_ON() macro usage there.
Also a similar warning is found but in another path:
Call Trace:
[< inline >] __dump_stack lib/dump_stack.c:15
[<ffffffff82be2c0d>] dump_stack+0x6f/0xa2 lib/dump_stack.c:50
[<ffffffff81355139>] warn_slowpath_common+0xd9/0x140 kernel/panic.c:482
[<ffffffff81355369>] warn_slowpath_null+0x29/0x30 kernel/panic.c:515
[<ffffffff8527e69a>] rawmidi_transmit_ack+0x24a/0x3b0 sound/core/rawmidi.c:1133
[<ffffffff8527e851>] snd_rawmidi_transmit_ack+0x51/0x80 sound/core/rawmidi.c:1163
[<ffffffff852d9046>] snd_virmidi_output_trigger+0x2b6/0x570 sound/core/seq/seq_virmidi.c:185
[< inline >] snd_rawmidi_output_trigger sound/core/rawmidi.c:150
[<ffffffff85285a0b>] snd_rawmidi_kernel_write1+0x4bb/0x760 sound/core/rawmidi.c:1252
[<ffffffff85287b73>] snd_rawmidi_write+0x543/0xb30 sound/core/rawmidi.c:1302
[<ffffffff817ba5f3>] __vfs_write+0x113/0x480 fs/read_write.c:528
[<ffffffff817bc087>] vfs_write+0x167/0x4a0 fs/read_write.c:577
[< inline >] SYSC_write fs/read_write.c:624
[<ffffffff817bf371>] SyS_write+0x111/0x220 fs/read_write.c:616
[<ffffffff86660276>] entry_SYSCALL_64_fastpath+0x16/0x7a arch/x86/entry/entry_64.S:185
In the former case, the reason is that virmidi has an open code
calling snd_rawmidi_transmit_ack() with the value calculated outside
the spinlock. We may use snd_rawmidi_transmit() in a loop just for
consuming the input data, but even there, there is a race between
snd_rawmidi_transmit_peek() and snd_rawmidi_tranmit_ack().
Similarly in the latter case, it calls snd_rawmidi_transmit_peek() and
snd_rawmidi_tranmit_ack() separately without protection, so they are
racy as well.
The patch tries to address these issues by the following ways:
- Introduce the unlocked versions of snd_rawmidi_transmit_peek() and
snd_rawmidi_transmit_ack() to be called inside the explicit lock.
- Rewrite snd_rawmidi_transmit() to be race-free (the former case).
- Make the split calls (the latter case) protected in the rawmidi spin
lock.
ALSA OSS sequencer spews a kernel error message ("ALSA: seq_oss: too
many applications") when user-space tries to open more than the
limit. This means that it can easily fill the log buffer.
Since it's merely a normal error, it's safe to suppress it via
pr_debug() instead.
ALSA sequencer OSS emulation code has a sanity check for currently
opened devices, but there is a thinko there, eventually it spews
warnings and skips the operation wrongly like:
WARNING: CPU: 1 PID: 7573 at sound/core/seq/oss/seq_oss_synth.c:311
ALSA dummy driver can switch the timer backend between system timer
and hrtimer via its hrtimer module option. This can be also switched
dynamically via sysfs, but it may lead to a memory corruption when
switching is done while a PCM stream is running; the stream instance
for the newly switched timer method tries to access the memory that
was allocated by another timer method although the sizes differ.
As the simplest fix, this patch just disables the switch via sysfs by
dropping the writable bit.
Some architectures like PowerPC can handle the maximum struct size in
an ioctl only up to 13 bits, and struct snd_compr_codec_caps used by
SNDRV_COMPRESS_GET_CODEC_CAPS ioctl overflows this limit. This
problem was revealed recently by a powerpc change, as it's now treated
as a fatal build error.
This patch is a stop-gap for that: for architectures with less than 14
bit ioctl struct size, get rid of the handling of the relevant ioctl.
We should provide an alternative equivalent ioctl code later, but for
now just paper over it. Luckily, the compress API hasn't been used on
such architectures, so the impact must be effectively zero.
Reviewed-by: Mark Brown <broonie@kernel.org> Acked-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On Broxton, to make sure the reset controller works properly,
MISCBDCGE bit (bit 6) in CGCTL (0x48) of PCI configuration space
need be cleared before reset and set back to 1 after reset.
Otherwise, it may prevent the CORB/RIRB logic from being reset.
Since the build of PCM timer may be disabled via Kconfig now, each
driver that provides a timer interface needs to set CONFIG_SND_TIMER
explicitly. Otherwise it may get a build error due to missing
symbol.
Fixes: 90bbaf66ee7b ('ALSA: timer: add config item to export PCM timer disabling for expert') Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The return type "unsigned int" was used by the get_formation_index function
despite of the aspect that it will eventually return a negative error code.
So, change to signed int and get index by reference in the parameters.
Done with the help of Coccinelle.
[Fix the missing braces suggested by Julia Lawall -- tiwai]
The 'umidi' object will be free'd on the error path by snd_usbmidi_free()
when tearing down the rawmidi interface. So we shouldn't try to free it
in snd_usbmidi_create() after having registered the rawmidi interface.
TEAC UD-501/UD-503/NT-503 fail to switch properly between different
rate/format. Similar to 'Playback Design', this patch corrects the
invalid clock source error for TEAC products and avoids complete
freeze of the usb interface of 503 series.
If CONFIG_TIME_LOW_RES is enabled we add a jiffie to the relative timeout to
prevent short sleeps, but we do not account for that in interfaces which
retrieve the remaining time.
Helge observed that timerfd can return a remaining time larger than the
relative timeout. That's not expected and breaks userland test programs.
Store the information that the timer was armed relative and provide functions
to adjust the remaining time. To avoid bloating the hrtimer struct make state
a u8, which as a bonus results in better code on x86 at least.
Reported-and-tested-by: Helge Deller <deller@gmx.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Cc: linux-m68k@lists.linux-m68k.org Cc: dhowells@redhat.com Link: http://lkml.kernel.org/r/20160114164159.273328486@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is not safe for an integrity profile to be changed while i/o is
in-flight in the queue. Prevent adding new disks or otherwise online
spares to an array if the device has an incompatible integrity profile.
The original change to the blk_integrity_unregister implementation in
md, commmit c7bfced9a671 "md: suspend i/o during runtime
blk_integrity_unregister" introduced an immediate hang regression.
This policy of disallowing changes the integrity profile once one has
been established is shared with DM.
Here is an abbreviated log from a test run that:
1/ Creates a degraded raid1 with an integrity-enabled device (pmem0s) [ 59.076127]
2/ Tries to add an integrity-disabled device (pmem1m) [ 90.489209]
3/ Retries with an integrity-enabled device (pmem1s) [ 205.671277]
[ 59.076127] md/raid1:md0: active with 1 out of 2 mirrors
[ 59.078302] md: data integrity enabled on md0
[..]
[ 90.489209] md0: incompatible integrity profile for pmem1m
[..]
[ 205.671277] md: super_written gets error=-5
[ 205.677386] md/raid1:md0: Disk failure on pmem1m, disabling device.
[ 205.677386] md/raid1:md0: Operation continuing on 1 devices.
[ 205.683037] RAID1 conf printout:
[ 205.684699] --- wd:1 rd:2
[ 205.685972] disk 0, wo:0, o:1, dev:pmem0s
[ 205.687562] disk 1, wo:1, o:1, dev:pmem1s
[ 205.691717] md: recovery of RAID array md0
Fixes: c7bfced9a671 ("md: suspend i/o during runtime blk_integrity_unregister") Cc: Mike Snitzer <snitzer@redhat.com> Reported-by: NeilBrown <neilb@suse.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a partial revert of commit ed8d1cf07cb16d ("[media] Export I2C
module alias information in missing drivers") that exported the module
aliases for the I2C drivers that were missing to make autoload to work.
But there is a bug report [0] that auto load of the ir-kbd-i2c driver
cause the Hauppauge HD-PVR driver to not behave correctly.
This is a hdpvr latent bug that was just exposed by ir-kbd-i2c module
autoloading working and will also happen if the I2C driver is built-in
or a user calls modprobe to load the module and register the driver.
But there is a regression experimented by users so until the real bug
is fixed, let's not export the module alias for the ir-kbd-i2c driver
even when this just masks the actual issue.
Fixes: ed8d1cf07cb1 ("[media] Export I2C module alias information in missing drivers") Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On a 64bit kernel build the compiler aligns the _sifields union in the
struct siginfo_t on a 64bit address. The __ARCH_SI_PREAMBLE_SIZE define
compensates for this alignment and thus fixes the wait testcase of the
strace package.
The symptoms of a wrong __ARCH_SI_PREAMBLE_SIZE value is that
_sigchld.si_stime variable is missed to be copied and thus after a
copy_siginfo() will have uninitialized values.
PA-RISC doesn't have atomic instructions to modify page table entries, so it
takes spinlock in the TLB handler and modifies the page table entry
non-atomically. If you modify the page table entry without the spinlock, you
may race with TLB handler on another CPU and your modification may be lost.
Protect against that with usage of purge_tlb_start() and purge_tlb_end() which
handles the TLB spinlock.
@console_may_schedule tracks whether console_sem was acquired through
lock or trylock. If the former, we're inside a sleepable context and
console_conditional_schedule() performs cond_resched(). This allows
console drivers which use console_lock for synchronization to yield
while performing time-consuming operations such as scrolling.
However, the actual console outputting is performed while holding
irq-safe logbuf_lock, so console_unlock() clears @console_may_schedule
before starting outputting lines. Also, only a few drivers call
console_conditional_schedule() to begin with. This means that when a
lot of lines need to be output by console_unlock(), for example on a
console registration, the task doing console_unlock() may not yield for
a long time on a non-preemptible kernel.
If this happens with a slow console devices, for example a serial
console, the outputting task may occupy the cpu for a very long time.
Long enough to trigger softlockup and/or RCU stall warnings, which in
turn pile more messages, sometimes enough to trigger the next cycle of
warnings incapacitating the system.
Fix it by making console_unlock() insert cond_resched() between lines if
@console_may_schedule.
Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Calvin Owens <calvinowens@fb.com> Acked-by: Jan Kara <jack@suse.com> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Kyle McMartin <kyle@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a max stack trace is discovered, the stack dump is saved. In order to
not record the overhead of the stack tracer, the ip of the traced function
is looked for within the dump. The trace is started from the location of
that function. But if for some reason the ip is not found, the entire stack
trace is then truncated. That's not very useful. Instead, print everything
if the ip of the traced function is not found within the trace.
This issue showed up on s390.
Link: http://lkml.kernel.org/r/20160129102241.1b3c9c04@gandalf.local.home Fixes: 72ac426a5bb0 ("tracing: Clean up stack tracing and fix fentry updates") Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com> Tested-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While cleaning the stacktrace code I unintentially changed the skip depth of
trace_buffer_unlock_commit_regs() from 0 to 6. kprobes uses this function,
and with skipping 6 call backs, it can easily produce no stack.
Commit 36e097a8a297 ("PCI: Split out bridge window override of minimum
allocation address") claimed to do no functional changes but unfortunately
did: The "min" variable is altered. At least the AVM A1 PCMCIA adapter was
no longer detected, breaking ISDN operation.
Use a local copy of "min" to restore the previous behaviour.
[bhelgaas: avoid gcc "?:" extension for portability and readability] Fixes: 36e097a8a297 ("PCI: Split out bridge window override of minimum allocation address") Signed-off-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On -RT and if kernel is booting with "threadirqs" cmd line parameter,
PCIe/PCI (MSI) IRQ cascade handlers (like dra7xx_pcie_msi_irq_handler())
will be forced threaded and, as result, will generate warnings like this:
WARNING: CPU: 1 PID: 82 at kernel/irq/handle.c:150 handle_irq_event_percpu+0x14c/0x174()
irq 460 handler irq_default_primary_handler+0x0/0x14 enabled interrupts
Backtrace:
(warn_slowpath_common) from (warn_slowpath_fmt+0x38/0x40)
(warn_slowpath_fmt) from (handle_irq_event_percpu+0x14c/0x174)
(handle_irq_event_percpu) from (handle_irq_event+0x84/0xb8)
(handle_irq_event) from (handle_simple_irq+0x90/0x118)
(handle_simple_irq) from (generic_handle_irq+0x30/0x44)
(generic_handle_irq) from (dra7xx_pcie_msi_irq_handler+0x7c/0x8c)
(dra7xx_pcie_msi_irq_handler) from (irq_forced_thread_fn+0x28/0x5c)
(irq_forced_thread_fn) from (irq_thread+0x128/0x204)
This happens because all of them invoke generic_handle_irq() from the
requested handler. generic_handle_irq() grabs raw_locks and thus needs to
run in raw-IRQ context.
This issue was originally reproduced on TI dra7-evem, but, as was
identified during discussion [1], other hosts can also suffer from this
issue. Fix all them at once by marking PCIe/PCI (MSI) IRQ cascade handlers
IRQF_NO_THREAD explicitly.
Commits such as commit 853f1c58c4b2 ("mtd: nand: omap2: show parent
device structure in sysfs") attempt to rely on the core MTD code to set
the MTD name based on the parent device. However, nand_base tries to set
a different default name according to the flash name (e.g., extracted
from the ONFI parameter page), which means NAND drivers will never make
use of the MTD defaults. This is not the intention of commit 853f1c58c4b2.
This results in problems when trying to use the cmdline partition
parser, since the MTD name is different than expected. Let's fix this by
providing a default NAND name, where possible.
Note that this is not really a great default name in the long run, since
this means that if there are multiple MTDs attached to the same
controller device, they will have the same name. But that is an existing
issue and requires future work on a better controller vs. flash chip
abstraction to fix properly.
Fixes: 853f1c58c4b2 ("mtd: nand: omap2: show parent device structure in sysfs") Reported-by: Heiko Schocher <hs@denx.de> Signed-off-by: Brian Norris <computersforpeace@gmail.com> Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com> Tested-by: Heiko Schocher <hs@denx.de> Cc: Heiko Schocher <hs@denx.de> Cc: Frans Klaver <fransklaver@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix the below Oops when trying to modprobe wlcore_spi.
The oops occurs because the wl1271_power_{off,on}()
function doesn't check the power() function pointer.
[ 23.665030] [<bf2581f0>] (wl12xx_set_power_on [wlcore]) from
[<bf25f7ac>] (wlcore_nvs_cb+0x118/0xa4c [wlcore])
[ 23.675604] [<bf25f7ac>] (wlcore_nvs_cb [wlcore]) from [<c04387ec>]
(request_firmware_work_func+0x30/0x58)
[ 23.685784] [<c04387ec>] (request_firmware_work_func) from
[<c0058e2c>] (process_one_work+0x1b4/0x4b4)
[ 23.695591] [<c0058e2c>] (process_one_work) from [<c0059168>]
(worker_thread+0x3c/0x4a4)
[ 23.704124] [<c0059168>] (worker_thread) from [<c005ee68>]
(kthread+0xd4/0xf0)
[ 23.711747] [<c005ee68>] (kthread) from [<c000f598>]
(ret_from_fork+0x14/0x3c)
[ 23.719357] Code: bad PC value
[ 23.722760] ---[ end trace 981be8510db9b3a9 ]---
Prevent oops by validationg power() pointer value before
calling the function.
Signed-off-by: Uri Mashiach <uri.mashiach@compulab.co.il> Acked-by: Igor Grinberg <grinberg@compulab.co.il> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The maximum chunks used by the function is
(SPI_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE + 1).
The original commands array had space for
(SPI_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE) commands.
When the last chunk is used (len > 4 * WSPI_MAX_CHUNK_SIZE), the last
command is stored outside the bounds of the commands array.
Oops 5 (page fault) is generated during current wl1271 firmware load
attempt:
root@debian-armhf:~# ifconfig wlan0 up
[ 294.312399] Unable to handle kernel paging request at virtual address 00203fc4
[ 294.320173] pgd = de528000
[ 294.323028] [00203fc4] *pgd=00000000
[ 294.326916] Internal error: Oops: 5 [#1] SMP ARM
[ 294.331789] Modules linked in: bnep rfcomm bluetooth ipv6 arc4 wl12xx
wlcore mac80211 musb_dsps cfg80211 musb_hdrc usbcore usb_common
wlcore_spi omap_rng rng_core musb_am335x omap_wdt cpufreq_dt thermal_sys
hwmon
[ 294.351838] CPU: 0 PID: 1827 Comm: ifconfig Not tainted 4.2.0-00002-g3e9ad27-dirty #78
[ 294.360154] Hardware name: Generic AM33XX (Flattened Device Tree)
[ 294.366557] task: dc9d6d40 ti: de550000 task.ti: de550000
[ 294.372236] PC is at __spi_validate+0xa8/0x2ac
[ 294.376902] LR is at __spi_sync+0x78/0x210
[ 294.381200] pc : [<c049c760>] lr : [<c049ebe0>] psr: 60000013
[ 294.381200] sp : de551998 ip : de5519d8 fp : 00200000
[ 294.393242] r10: de551c8c r9 : de5519d8 r8 : de3a9000
[ 294.398730] r7 : de3a9258 r6 : de3a9400 r5 : de551a48 r4 : 00203fbc
[ 294.405577] r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : de3a9000
[ 294.412420] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM
Segment user
[ 294.419918] Control: 10c5387d Table: 9e528019 DAC: 00000015
[ 294.425954] Process ifconfig (pid: 1827, stack limit = 0xde550218)
[ 294.432437] Stack: (0xde551998 to 0xde552000)
...
[ 294.883613] [<c049c760>] (__spi_validate) from [<c049ebe0>]
(__spi_sync+0x78/0x210)
[ 294.891670] [<c049ebe0>] (__spi_sync) from [<bf036598>]
(wl12xx_spi_raw_write+0xfc/0x148 [wlcore_spi])
[ 294.901661] [<bf036598>] (wl12xx_spi_raw_write [wlcore_spi]) from
[<bf21c694>] (wlcore_boot_upload_firmware+0x1ec/0x458 [wlcore])
[ 294.914038] [<bf21c694>] (wlcore_boot_upload_firmware [wlcore]) from
[<bf24532c>] (wl12xx_boot+0xc10/0xfac [wl12xx])
[ 294.925161] [<bf24532c>] (wl12xx_boot [wl12xx]) from [<bf20d5cc>]
(wl1271_op_add_interface+0x5b0/0x910 [wlcore])
[ 294.936364] [<bf20d5cc>] (wl1271_op_add_interface [wlcore]) from
[<bf15c4ac>] (ieee80211_do_open+0x44c/0xf7c [mac80211])
[ 294.947963] [<bf15c4ac>] (ieee80211_do_open [mac80211]) from
[<c0537978>] (__dev_open+0xa8/0x110)
[ 294.957307] [<c0537978>] (__dev_open) from [<c0537bf8>]
(__dev_change_flags+0x88/0x148)
[ 294.965713] [<c0537bf8>] (__dev_change_flags) from [<c0537cd0>]
(dev_change_flags+0x18/0x48)
[ 294.974576] [<c0537cd0>] (dev_change_flags) from [<c05a55a0>]
(devinet_ioctl+0x6b4/0x7d0)
[ 294.983191] [<c05a55a0>] (devinet_ioctl) from [<c0517040>]
(sock_ioctl+0x1e4/0x2bc)
[ 294.991244] [<c0517040>] (sock_ioctl) from [<c017d378>]
(do_vfs_ioctl+0x420/0x6b0)
[ 294.999208] [<c017d378>] (do_vfs_ioctl) from [<c017d674>]
(SyS_ioctl+0x6c/0x7c)
[ 295.006880] [<c017d674>] (SyS_ioctl) from [<c000f4c0>]
(ret_fast_syscall+0x0/0x54)
[ 295.014835] Code: e1550004e24440340a00007de5953018 (e5942008)
[ 295.021544] ---[ end trace 66ed188198f4e24e ]---
Signed-off-by: Uri Mashiach <uri.mashiach@compulab.co.il> Acked-by: Igor Grinberg <grinberg@compulab.co.il> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When recovery master down, dlm_do_local_recovery_cleanup() only remove
the $RECOVERY lock owned by dead node, but do not clear the refmap bit.
Which will make umount thread falling in dead loop migrating $RECOVERY
to the dead node.
Signed-off-by: xuejiufei <xuejiufei@huawei.com> Reviewed-by: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We have found that migration source will trigger a BUG that the refcount
of mle is already zero before put when the target is down during
migration. The situation is as follows:
dlm_migrate_lockres
dlm_add_migration_mle
dlm_mark_lockres_migrating
dlm_get_mle_inuse
<<<<<< Now the refcount of the mle is 2.
dlm_send_one_lockres and wait for the target to become the
new master.
<<<<<< o2hb detect the target down and clean the migration
mle. Now the refcount is 1.
dlm_migrate_lockres woken, and put the mle twice when found the target
goes down which trigger the BUG with the following message:
"ERROR: bad mle: ".
Signed-off-by: Jiufei Xue <xuejiufei@huawei.com> Reviewed-by: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many codecs, typically found on Realtek codecs, have the analog
loopback path merged to the secondary input of the middle of the
output paths. Currently, we don't offer the dynamic switching in such
configuration but let each loopback path mute by itself.
This should work well in theory, but in reality, we often see that
such a dead loopback path causes some background noises even if all
the elements get muted. Such a problem has been fixed by adding the
quirk accordingly to disable aamix, and it's the right fix, per se.
The only problem is that it's not so trivial to achieve it; user needs
to pass a hint string via patch module option or sysfs.
This patch gives a bit improvement on the situation: it adds "Loopback
Mixing" control element for such codecs like other codecs (e.g. IDT or
VIA codecs) with the individual loopback paths. User can turn on/off
the loopback path simply via a mixer app.
For keeping the compatibility, the loopback is still enabled on these
codecs. But user can try to turn it off if experiencing a suspicious
background or click noise on the fly, then build a static fixup later
once after the problem is addressed.
Other than the addition of the loopback enable/disablement control,
there should be no changes.
After commit e36f62042880(block: split bios to maxpossible length),
bio can be splitted in the middle of a vector entry, then it
is easy to split out one bio which size isn't aligned with block
size, especially when the block size is bigger than 512.
This patch fixes the issue by making the max io size aligned
to logical block size.
Fixes: e36f62042880(block: split bios to maxpossible length) Reported-by: Stefan Haberland <sth@linux.vnet.ibm.com> Cc: Keith Busch <keith.busch@intel.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since b8b2c7d845d5, platform_drv_probe() is called for all platform
devices. If drv->probe is NULL, and dev_pm_domain_attach() fails,
platform_drv_probe() will return the error code from dev_pm_domain_attach().
This causes real_probe() to enter the "probe_failed" path and set
dev->driver to NULL. Before b8b2c7d845d5, real_probe() would assume
success if both dev->bus->probe and drv->probe were missing. As a result,
a device and driver could be "bound" together just by matching their names;
this doesn't work any more after b8b2c7d845d5.
This may cause problems later for certain usage of platform_driver_register()
and platform_device_register_simple(). I observed a panic while loading
the tpm_tis driver with parameter "force=1" (i.e. registering tpm_tis as
a platform driver), because tpm_tis_init's assumption that the device
returned by platform_device_register_simple() was bound didn't hold any more
(tpmm_chip_alloc() dereferences chip->pdev->driver, causing panic).
This patch restores the previous (4.3.0 and earlier) behavior of
platform_drv_probe() in the case when the associated platform driver has
no "probe" function.
Fixes: b8b2c7d845d5 ("base/platform: assert that dev_pm_domain callbacks are called unconditionally") Signed-off-by: Martin Wilck <Martin.Wilck@ts.fujitsu.com> Cc: Martin Fuzzey <mfuzzey@parkeon.com> Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The critical section protected by usbhid->lock in hid_ctrl() is too
big and because of this it causes a recursive deadlock. "Too big" means
the case statement and the call to hid_input_report() do not need to be
protected by the spinlock (no URB operations are done inside them).
The deadlock happens because in certain rare cases drivers try to grab
the lock while handling the ctrl irq which grabs the lock before them
as described above. For example newer wacom tablets like 056a:033c try
to reschedule proximity reads from wacom_intuos_schedule_prox_event()
calling hid_hw_request() -> usbhid_request() -> usbhid_submit_report()
which tries to grab the usbhid lock already held by hid_ctrl().
There are two ways to get out of this deadlock:
1. Make the drivers work "around" the ctrl critical region, in the
wacom case for ex. by delaying the scheduling of the proximity read
request itself to a workqueue.
2. Shrink the critical region so the usbhid lock protects only the
instructions which modify usbhid state, calling hid_input_report()
with the spinlock unlocked, allowing the device driver to grab the
lock first, finish and then grab the lock afterwards in hid_ctrl().
NFS on a 2 node ocfs2 cluster each node exporting dir. The lock causing
the hang is the global bit map inode lock. Node 1 is master, has the
lock granted in PR mode; Node 2 is in the converting list (PR -> EX).
There are no holders of the lock on the master node so it should
downconvert to NL and grant EX to node 2 but that does not happen.
BLOCKED + QUEUED in lock res are set and it is on osb blocked list.
Threads are waiting in __ocfs2_cluster_lock on BLOCKED. One thread
wants EX, rest want PR. So it is as though the downconvert thread needs
to be kicked to complete the conv.
The hang is caused by an EX req coming into __ocfs2_cluster_lock on the
heels of a PR req after it sets BUSY (drops l_lock, releasing EX
thread), forcing the incoming EX to wait on BUSY without doing anything.
PR has called ocfs2_dlm_lock, which sets the node 1 lock from NL -> PR,
queues ast.
At this time, upconvert (PR ->EX) arrives from node 2, finds conflict
with node 1 lock in PR, so the lock res is put on dlm thread's dirty
listt.
After ret from ocf2_dlm_lock, PR thread now waits behind EX on BUSY till
awoken by ast.
Now it is dlm_thread that serially runs dlm_shuffle_lists, ast, bast, in
that order. dlm_shuffle_lists ques a bast on behalf of node 2 (which
will be run by dlm_thread right after the ast). ast does its part, sets
UPCONVERT_FINISHING, clears BUSY and wakes its waiters. Next,
dlm_thread runs bast. It sets BLOCKED and kicks dc thread. dc thread
runs ocfs2_unblock_lock, but since UPCONVERT_FINISHING set, skips doing
anything and reques.
Inside of __ocfs2_cluster_lock, since EX has been waiting on BUSY ahead
of PR, it wakes up first, finds BLOCKED set and skips doing anything but
clearing UPCONVERT_FINISHING (which was actually "meant" for the PR
thread), and this time waits on BLOCKED. Next, the PR thread comes out
of wait but since UPCONVERT_FINISHING is not set, it skips updating the
l_ro_holders and goes straight to wait on BLOCKED. So there, we have a
hang! Threads in __ocfs2_cluster_lock wait on BLOCKED, lock res in osb
blocked list. Only when dc thread is awoken, it will run
ocfs2_unblock_lock and things will unhang.
One way to fix this is to wake the dc thread on the flag after clearing
UPCONVERT_FINISHING
Orabug: 20933419 Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com> Reviewed-by: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Joseph Qi <joseph.qi@huawei.com> Cc: Eric Ren <zren@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This splits bio in the middle of a vector to form the largest possible
bio at the h/w's desired alignment, and guarantees the bio being split
will have some data.
The criteria for splitting is changed from the max sectors to the h/w's
optimal sector alignment if it is provided. For h/w that advertise their
block storage's underlying chunk size, it's a big performance win to not
submit commands that cross them. If sector alignment is not provided,
this patch uses the max sectors as before.
This addresses the performance issue commit d380561113 attempted to
fix, but was reverted due to splitting logic error.
Signed-off-by: Keith Busch <keith.busch@intel.com> Cc: Jens Axboe <axboe@fb.com> Cc: Ming Lei <tom.leiming@gmail.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 2d8ae84fbc32, nothing is bumping lo->plh_block_lgets in the
layoutreturn path, so it should not be touched in nfs4_layoutreturn_release
either.
sun4i-ss implementaton of md5/sha1 is via ahash algorithms.
Commit 8996eafdcbad ("crypto: ahash - ensure statesize is non-zero")
made impossible to load them without giving statesize. This patch
specifiy statesize for sha1 and md5.
The Performance Monitors extension is an optional feature of the
AArch64 architecture, therefore, in order to access Performance
Monitors registers safely, the kernel should detect the architected
PMU unit presence through the ID_AA64DFR0_EL1 register PMUVer field
before accessing them.
This patch implements a guard by reading the ID_AA64DFR0_EL1 register
PMUVer field to detect the architected PMU presence and prevent accessing
PMU system registers if the Performance Monitors extension is not
implemented in the core.
Cc: Peter Maydell <peter.maydell@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Fixes: 60792ad349f3 ("arm64: kernel: enforce pmuserenr_el0 initialization and restore") Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The pmuserenr_el0 register value is architecturally UNKNOWN on reset.
Current kernel code resets that register value iff the core pmu device is
correctly probed in the kernel. On platforms with missing DT pmu nodes (or
disabled perf events in the kernel), the pmu is not probed, therefore the
pmuserenr_el0 register is not reset in the kernel, which means that its
value retains the reset value that is architecturally UNKNOWN (system
may run with eg pmuserenr_el0 == 0x1, which means that PMU counters access
is available at EL0, which must be disallowed).
This patch adds code that resets pmuserenr_el0 on cold boot and restores
it on core resume from shutdown, so that the pmuserenr_el0 setup is
always enforced in the kernel.
Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In paging_init, we allocate the zero page, memset it to zero and then
point TTBR0 to it in order to avoid speculative fetches through the
identity mapping.
In order to guarantee that the freshly zeroed page is indeed visible to
the page table walker, we need to execute a dsb instruction prior to
writing the TTBR.
Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
projects / karo-tx-linux.git / log