A Halo Core DSP has a memory protection unit that can trap and signal
memory access faults. This patch adds a function that dumps the fault
information.
The interrupt reaches the host via the parent codec interrupt controller
so this fault function is exported to be called by the codec driver.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The Halo core is a new generation of audio DSP architecture from
Cirrus Logic. A new iteration of the WMFW file format (v3) is also
added, for this new architecture. Currently this format is not
supported on the old ADSP2 architecture however support may be
added for it in the future.
Signed-off-by: Wen Shi <wenshi@opensource.cirrus.com>
Signed-off-by: Piotr Stankiewicz <piotrs@opensource.cirrus.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Change the signature of mtk_regmap_update_bits to also take a shift, and
warn when reg >= 0 but shift < 0. This reduce the code repetition
on the calling side, and prevent future UBSAN warning when some of the
xxx_shift and xxx_reg are both set to -1.
Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
In sound/soc/mediatek/common/mtk-afe-fe-dai.c, when xxx_reg is -1, it's
a no-op to call mtk_regmap_update_bits, but since both xxx_reg and
xxx_shift are set to -1, the (1 << xxx_shift) in the argument would
trigger a UBSAN warning.
Fix the warning by setting those xxx_shift to 0 instead.
Note that since the code explicitly checks .mono_shift >= 0 and
.fs_shift >= 0 before using them in '<<' operator, those two members are
not set to 0.
Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
In preparation for the addition of more types of DSP core refactor the
handling of DSP specific operations such as starting the memory or
enabling the core into a set of callbacks. This should make it easier to
add new core types and allow for more code reuse between them.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There is no need to duplicate this code for both ADSP1 and 2 as the
handling is exactly the same.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
In preparation for further additions refactor the reading of the
firmware status.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The original wm_adsp2_early_event took an additional frequency
argument for clocking control so could not be used directly as a
DAPM callback. But this setup could equally be done by the codec
driver function wrapping wm_adsp2_early event. In preparation
for adding support for new core types wm_adsp2_set_dspclk has
been exported, and the freq argument removed so that it can
be used directly as a DAPM callback.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This function is not presently called from outside the adsp code and nor
should it be, as such stop exporting it.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
If a watchdog timeout is received from the DSP it is safe to assume the
DSP is not functioning anymore and as such any active compressed streams
should be put into an error state.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Best to lock across handling the bus error to ensure the DSP doesn't
change power state as we are reading the status registers.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
During recent logging improvements it seems two error messages lost
their updates during patch application/rebasing. Add these back in.
Fixes: 0d3fba3e7a ("ASoC: wm_adsp: Improve logging messages")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Previously support was added to allow streams to be stopped and
started again without the DSP being power cycled and this was done
by clearing the buffer state in trigger start. Another supported
use-case is using the DSP for a trigger event then opening the
compressed stream later to receive the audio, unfortunately clearing
the buffer state in trigger start destroys the data received
from such a trigger. Correct this issue by moving the call to
wm_adsp_buffer_clear to be in trigger stop instead.
Fixes: 61fc060c40 ("ASoC: wm_adsp: Support streams which can start/stop with DSP active")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some strings are allocated by kstrdup, but not freed when error
happened.
Signed-off-by: Bard liao <yung-chuan.liao@linux.intel.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The stream_name is allocated by kstrdup. We have to free it when the
dai is removed or return from error.
Signed-off-by: Bard liao <yung-chuan.liao@linux.intel.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
It is parsing mclk_fs at many places, but it should be
same operation. This patch adds graph_parse_mclk_fs()
and parse it.
This patch also renames similar function graph_get_conversion()
to graph_parse_convert().
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
use same naming rule, and this patch add missing of_node_put() on it
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
It is parsing mclk_fs at many places, but it should be
same operation. This patch adds simple_parse_mclk_fs()
and parse it.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
If ASRC turns on, HW will use clk_dac as the reference clock
whether recording or playback.
Both of clk_dac and clk_adc should set proper clock while using ASRC.
Signed-off-by: Shuming Fan <shumingf@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The jack type detection needs the main bias power of analog.
The modification makes sure the main bias power on/off while jack plug/unplug.
Signed-off-by: Shuming Fan <shumingf@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The IRQ function may not work when system suspend.
We remove snd_soc_dapm_force_enable_pin function call to
make sure the bias off when idle and run into suspend/resume function.
Signed-off-by: Shuming Fan <shumingf@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Skip for i2s5 in mck_disable which is also bypassed in mck_enable.
Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add BYT_RT5651_JD_NOT_INV quirk for devices with an inverted
(active-high instead of the normal active-low) jack-detect switch.
And add a quirk for the Complet Electro Serv MY8307 tablet which has
an inverted jack-detect switch (and a mono-speaker).
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some boards use a jack-receptacle with a switch which reports the
jack-inserted status as active-high, rather then the standard active-low
reporting most jacks use.
This commit adds support for it. This is activated by a boolean
"realtek,jack-detect-not-inverted" device-property. The not-inverted
in the device-property name, rather then active-high, was chosen to keep
the device-property naming consistent with the rt5640 codec driver.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add suspend and resume sleep callbacks to STM32 SPDIFRX driver,
to support system low power modes.
Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The dpcm get from fe_clients/be_clients
may be free before use
Add a spin lock at snd_soc_card level,
to protect the dpcm instance.
The lock may be used in atomic context, so use spin lock.
possible race condition between
void dpcm_be_disconnect(
...
list_del(&dpcm->list_be);
list_del(&dpcm->list_fe);
kfree(dpcm);
...
and
for_each_dpcm_fe()
for_each_dpcm_be*()
race condition example
Thread 1:
snd_soc_dapm_mixer_update_power()
-> soc_dpcm_runtime_update()
-> dpcm_be_disconnect()
-> kfree(dpcm);
Thread 2:
dpcm_fe_dai_trigger()
-> dpcm_be_dai_trigger()
-> snd_soc_dpcm_can_be_free_stop()
-> if (dpcm->fe == fe)
Excpetion Scenario:
two FE link to same BE
FE1 -> BE
FE2 ->
Thread 1: switch of mixer between FE2 -> BE
Thread 2: pcm_stop FE1
Exception:
Unable to handle kernel paging request at virtual address dead0000000000e0
pc=<> [<ffffff8960e2cd10>] dpcm_be_dai_trigger+0x29c/0x47c
sound/soc/soc-pcm.c:3226
if (dpcm->fe == fe)
lr=<> [<ffffff8960e2f694>] dpcm_fe_dai_do_trigger+0x94/0x26c
Backtrace:
[<ffffff89602dba80>] notify_die+0x68/0xb8
[<ffffff896028c7dc>] die+0x118/0x2a8
[<ffffff89602a2f84>] __do_kernel_fault+0x13c/0x14c
[<ffffff89602a27f4>] do_translation_fault+0x64/0xa0
[<ffffff8960280cf8>] do_mem_abort+0x4c/0xd0
[<ffffff8960282ad0>] el1_da+0x24/0x40
[<ffffff8960e2cd10>] dpcm_be_dai_trigger+0x29c/0x47c
[<ffffff8960e2f694>] dpcm_fe_dai_do_trigger+0x94/0x26c
[<ffffff8960e2edec>] dpcm_fe_dai_trigger+0x3c/0x44
[<ffffff8960de5588>] snd_pcm_do_stop+0x50/0x5c
[<ffffff8960dded24>] snd_pcm_action+0xb4/0x13c
[<ffffff8960ddfdb4>] snd_pcm_drop+0xa0/0x128
[<ffffff8960de69bc>] snd_pcm_common_ioctl+0x9d8/0x30f0
[<ffffff8960de1cac>] snd_pcm_ioctl_compat+0x29c/0x2f14
[<ffffff89604c9d60>] compat_SyS_ioctl+0x128/0x244
[<ffffff8960283740>] el0_svc_naked+0x34/0x38
[<ffffffffffffffff>] 0xffffffffffffffff
Signed-off-by: KaiChieh Chuang <kaichieh.chuang@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some amplifier may not have a GPIO to control the power, but instead simply
rely on the regulator to power up and down the amplifier.
In order to support those setups, let's make the GPIO optional.
Signed-off-by: Mylène Josserand <mylene.josserand@bootlin.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
If SoC has extended Audio DMAC peri peri address,
DT needs to select it.
Otherwise, it can select normal Audio DMAC peri peri address.
Extended Audio DMAC peri peri address can use BUSIF4-7,
normal address can't.
Reported-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Mark Brown <broonie@kernel.org>
reg is missing "Audio DMAC peri peri" part,
and reg-name itself is missing at Document.
This patch add these.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull x86 asm updates from Thomas Gleixner:
"Two cleanup patches removing dead conditionals and unused code"
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/asm: Remove unused __constant_c_x_memset() macro and inlines
x86/asm: Remove dead __GNUC__ conditionals
Pull perf fixes from Thomas Gleixner:
"Three fixes for the fallout from the TSX errata workaround:
- Prevent memory corruption caused by a unchecked out of bound array
index.
- Two trivial fixes to address compiler warnings"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Make dev_attr_allow_tsx_force_abort static
perf/x86: Fixup typo in stub functions
perf/x86/intel: Fix memory corruption
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Merge tag 'for-linus-5.1b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fix from Juergen Gross:
"A fix for a Xen bug introduced by David's series for excluding
ballooned pages in vmcores"
* tag 'for-linus-5.1b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/balloon: Fix mapping PG_offline pages to user space
Two fixes (leak on invalid mount argument and possible deadlock on
i_size update on 32bit smp) and a fall-through warning cleanup
----------------------------------------------------------------
Gustavo A. R. Silva (1):
9p: mark expected switch fall-through
Hou Tao (1):
9p: use inode->i_lock to protect i_size_write() under 32-bit
zhengbin (1):
9p/net: fix memory leak in p9_client_create
fs/9p/v9fs_vfs.h | 23 +++++++++++++++++++++--
fs/9p/vfs_file.c | 6 +++++-
fs/9p/vfs_inode.c | 23 +++++++++++------------
fs/9p/vfs_inode_dotl.c | 27 ++++++++++++++-------------
fs/9p/vfs_super.c | 4 ++--
net/9p/client.c | 2 +-
net/9p/trans_xen.c | 2 +-
7 files changed, 55 insertions(+), 32 deletions(-)
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Merge tag '9p-for-5.1' of git://github.com/martinetd/linux
Pull 9p updates from Dominique Martinet:
"Here is a 9p update for 5.1; there honestly hasn't been much.
Two fixes (leak on invalid mount argument and possible deadlock on
i_size update on 32bit smp) and a fall-through warning cleanup"
* tag '9p-for-5.1' of git://github.com/martinetd/linux:
9p/net: fix memory leak in p9_client_create
9p: use inode->i_lock to protect i_size_write() under 32-bit
9p: mark expected switch fall-through
When this .gitignore was added, lxdialog was an independent hostprogs-y.
Now that all objects in lxdialog/ are directly linked to mconf, the
lxdialog is no longer generated.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Currently, every arch/*/include/uapi/asm/Kbuild explicitly includes
the common Kbuild.asm file. Factor out the duplicated include directives
to scripts/Makefile.asm-generic so that no architecture would opt out
of the mandatory-y mechanism.
um is not forced to include mandatory-y since it is a very exceptional
case which does not support UAPI.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The generic-y is redundant under the following condition:
- arch has its own implementation
- the same header is added to generated-y
- the same header is added to mandatory-y
If a redundant generic-y is found, the warning like follows is displayed:
scripts/Makefile.asm-generic:20: redundant generic-y found in arch/arm/include/asm/Kbuild: timex.h
I fixed up arch Kbuild files found by this.
Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
During a simple no-op (nothing changed) build I saw 39 invocations of
the C compiler with the argument "-print-file-name=include". We don't
need to call the C compiler 39 times for this--one time will suffice.
Let's change NOSTDINC_FLAGS to a simply expanded variable to avoid
this since there doesn't appear to be any reason it should be
recursively expanded.
On my build this shaved ~400 ms off my "no-op" build.
Note that the recursive expansion seems to date back to the (really
old) commit e8f5bdb02c ("[PATCH] Makefile include path ordering").
It's a little unclear to me if the point of that patch was to switch
the variable to be recursively expanded (which it did) or to avoid
directly assigning to NOSTDINC_FLAGS (AKA to switch to +=) because
someone else (out of tree?) was setting it. I presume later since if
the only goal was to switch to recursive expansion the patch would
have just removed the ":".
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
* The man page for dpkg-source(1) notes:
> -b, --build directory [format-specific-parameters]
> Build a source package (--build since dpkg 1.17.14).
> <...>
>
> dpkg-source will build the source package with the first
> format found in this ordered list: the format indicated
> with the --format command line option, the format
> indicated in debian/source/format, “1.0”. The fallback
> to “1.0” is deprecated and will be removed at some point
> in the future, you should always document the desired
> source format in debian/source/format. See section
> SOURCE PACKAGE FORMATS for an extensive description of
> the various source package formats.
Thus it would be more foolproof to explicitly use 1.0 (as we always
did) than to rely on dpkg-source's defaults.
* In a similar vein, debian/rules is not made executable by mkdebian,
and dpkg-source warns about that but still silently fixes the file.
Let's be explicit once again.
Signed-off-by: Arseny Maslennikov <ar@cs.msu.ru>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The of_find_device_by_node() takes a reference to the underlying device
structure, we should release that reference.
The implementation of this semantic code search is:
In a function, for a local variable returned by calling
of_find_device_by_node(),
a, if it is released by a function such as
put_device()/of_dev_put()/platform_device_put() after the last use,
it is considered that there is no reference leak;
b, if it is passed back to the caller via
dev_get_drvdata()/platform_get_drvdata()/get_device(), etc., the
reference will be released in other functions, and the current function
also considers that there is no reference leak;
c, for the rest of the situation, the current function should release the
reference by calling put_device, this code search will report the
corresponding error message.
By using this semantic code search, we have found some object reference leaks,
such as:
commit 11907e9d35 ("ASoC: fsl-asoc-card: fix object reference leaks in
fsl_asoc_card_probe")
commit a12085d139 ("mtd: rawnand: atmel: fix possible object reference leak")
commit 11493f2685 ("mtd: rawnand: jz4780: fix possible object reference leak")
There are still dozens of reference leaks in the current kernel code.
Further, for the case of b, the object returned to other functions may also
have a reference leak, we will continue to develop other cocci scripts to
further check the reference leak.
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Reviewed-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Markus Elfring <Markus.Elfring@web.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
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Merge tag 'pidfd-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull pidfd system call from Christian Brauner:
"This introduces the ability to use file descriptors from /proc/<pid>/
as stable handles on struct pid. Even if a pid is recycled the handle
will not change. For a start these fds can be used to send signals to
the processes they refer to.
With the ability to use /proc/<pid> fds as stable handles on struct
pid we can fix a long-standing issue where after a process has exited
its pid can be reused by another process. If a caller sends a signal
to a reused pid it will end up signaling the wrong process.
With this patchset we enable a variety of use cases. One obvious
example is that we can now safely delegate an important part of
process management - sending signals - to processes other than the
parent of a given process by sending file descriptors around via scm
rights and not fearing that the given process will have been recycled
in the meantime. It also allows for easy testing whether a given
process is still alive or not by sending signal 0 to a pidfd which is
quite handy.
There has been some interest in this feature e.g. from systems
management (systemd, glibc) and container managers. I have requested
and gotten comments from glibc to make sure that this syscall is
suitable for their needs as well. In the future I expect it to take on
most other pid-based signal syscalls. But such features are left for
the future once they are needed.
This has been sitting in linux-next for quite a while and has not
caused any issues. It comes with selftests which verify basic
functionality and also test that a recycled pid cannot be signaled via
a pidfd.
Jon has written about a prior version of this patchset. It should
cover the basic functionality since not a lot has changed since then:
https://lwn.net/Articles/773459/
The commit message for the syscall itself is extensively documenting
the syscall, including it's functionality and extensibility"
* tag 'pidfd-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
selftests: add tests for pidfd_send_signal()
signal: add pidfd_send_signal() syscall
* Replace the /sys/class/dax device model with /sys/bus/dax, and include
a compat driver so distributions can opt-in to the new ABI.
* Allow for an alternative driver for the device-dax address-range
* Introduce the 'kmem' driver to hotplug / assign a device-dax
address-range to the core-mm.
* Arrange for the device-dax target-node to be onlined so that the newly
added memory range can be uniquely referenced by numa apis.
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Merge tag 'devdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull device-dax updates from Dan Williams:
"New device-dax infrastructure to allow persistent memory and other
"reserved" / performance differentiated memories, to be assigned to
the core-mm as "System RAM".
Some users want to use persistent memory as additional volatile
memory. They are willing to cope with potential performance
differences, for example between DRAM and 3D Xpoint, and want to use
typical Linux memory management apis rather than a userspace memory
allocator layered over an mmap() of a dax file. The administration
model is to decide how much Persistent Memory (pmem) to use as System
RAM, create a device-dax-mode namespace of that size, and then assign
it to the core-mm. The rationale for device-dax is that it is a
generic memory-mapping driver that can be layered over any "special
purpose" memory, not just pmem. On subsequent boots udev rules can be
used to restore the memory assignment.
One implication of using pmem as RAM is that mlock() no longer keeps
data off persistent media. For this reason it is recommended to enable
NVDIMM Security (previously merged for 5.0) to encrypt pmem contents
at rest. We considered making this recommendation an actively enforced
requirement, but in the end decided to leave it as a distribution /
administrator policy to allow for emulation and test environments that
lack security capable NVDIMMs.
Summary:
- Replace the /sys/class/dax device model with /sys/bus/dax, and
include a compat driver so distributions can opt-in to the new ABI.
- Allow for an alternative driver for the device-dax address-range
- Introduce the 'kmem' driver to hotplug / assign a device-dax
address-range to the core-mm.
- Arrange for the device-dax target-node to be onlined so that the
newly added memory range can be uniquely referenced by numa apis"
NOTE! I'm not entirely happy with the whole "PMEM as RAM" model because
we currently have special - and very annoying rules in the kernel about
accessing PMEM only with the "MC safe" accessors, because machine checks
inside the regular repeat string copy functions can be fatal in some
(not described) circumstances.
And apparently the PMEM modules can cause that a lot more than regular
RAM. The argument is that this happens because PMEM doesn't necessarily
get scrubbed at boot like RAM does, but that is planned to be added for
the user space tooling.
Quoting Dan from another email:
"The exposure can be reduced in the volatile-RAM case by scanning for
and clearing errors before it is onlined as RAM. The userspace tooling
for that can be in place before v5.1-final. There's also runtime
notifications of errors via acpi_nfit_uc_error_notify() from
background scrubbers on the DIMM devices. With that mechanism the
kernel could proactively clear newly discovered poison in the volatile
case, but that would be additional development more suitable for v5.2.
I understand the concern, and the need to highlight this issue by
tapping the brakes on feature development, but I don't see PMEM as RAM
making the situation worse when the exposure is also there via DAX in
the PMEM case. Volatile-RAM is arguably a safer use case since it's
possible to repair pages where the persistent case needs active
application coordination"
* tag 'devdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
device-dax: "Hotplug" persistent memory for use like normal RAM
mm/resource: Let walk_system_ram_range() search child resources
mm/memory-hotplug: Allow memory resources to be children
mm/resource: Move HMM pr_debug() deeper into resource code
mm/resource: Return real error codes from walk failures
device-dax: Add a 'modalias' attribute to DAX 'bus' devices
device-dax: Add a 'target_node' attribute
device-dax: Auto-bind device after successful new_id
acpi/nfit, device-dax: Identify differentiated memory with a unique numa-node
device-dax: Add /sys/class/dax backwards compatibility
device-dax: Add support for a dax override driver
device-dax: Move resource pinning+mapping into the common driver
device-dax: Introduce bus + driver model
device-dax: Start defining a dax bus model
device-dax: Remove multi-resource infrastructure
device-dax: Kill dax_region base
device-dax: Kill dax_region ida
