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Sof hda update 0723 - #50

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Sof hda update 0723#50
keyonjie wants to merge 21 commits into
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keyonjie:sof-hda

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updates:

  1. refine Kconfig.
  2. fix hdmi codec probing failed issue.

rakeshughrejaand others added 20 commits July 20, 2018 15:10
As per HDA spec section 4.3 - Codec Discovery, the software shall wait
for atleast 521usec for codec to respond after link reset.
With the multi-link capability each link is turned ON/OFF individually.
Link controller drives reset signal when it is turned ON.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
…e instead
This patch removes the hdac_ext_device structure. The legacy and
enhanced HDaudio capabilities can be handled in a backward-compatible
way without separate definitions.
Follow-up patches in this series handle the bus and driver definitions.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
This patch removes the hdac_ext_bus structure. The legacy and
enhanced HDaudio capabilities can be handled in a backward-compatible
way without separate definitions.
Follow-up patches in this series handle the driver definition.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
…nstead
This patch removes the hdac_ext_driver structure. The legacy and
enhanced HDaudio capabilities can be handled in a backward-compatible
way without separate definitions.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Split snd_hda_codec_new into two separate functions.
snd_hda_codec_device_init allocates memory and registers with bus.
snd_hda_codec_device_new initialializes the fields and performs
snd_device_new. This enables reuse of legacy HDA codec drivers as ASoC
codec drivers.
In addition mark some functions with EXPORT_SYMBOL_GPL so that it can
be called by ASoC wrapper around the legacy HDA driver (hdac_hda).
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Remove memory allocation within snd_hdac_ext_bus_device_init, to make
its behaviour identical to snd_hdac_bus_device_init. So that caller
can allocate the parent data structure containing hdac_device.
This API change helps in reusing the legacy HDA codec drivers with
ASoC platform drivers.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Add extended ops in the hdac_bus to allow calling the ASoC HDAC library
ops to reuse the legacy HDA codec drivers with ASoC framework.
Extended ops are used by the legacy codec drivers to call into
hdac_hda library, in the subsequent patches..
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Add machine driver for Intel platforms (SKL/KBL/BXT/APL) with
HDA and iDisp codecs. This patch adds support for only iDisp (HDMI/DP)
codec. In the following patches support for HDA codecs will be added.
This should work for other Intel platforms as well e.g. GLK,CNL
however this series is not tested on all the platforms.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
When no I2S based codec entries are found in the BIOS, check if there are
any HDA codecs detected on the bus. Based on the number of codecs found
take appropriate action in machine driver. If there are two HDA codecs
i.e. iDisp + HDA found on the bus, register DAIs and DAI links for both.
If only one codec i.e. iDisp is found then load only iDisp machine driver.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
Add support for HDA BE DAIs in SKL platform driver.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Use hda_bus instead of hdac_bus in the SKL ASoC platform driver to enable
reuse of legacy HDA codec drivers.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
This patch adds a kernel module which is used by the legacy HDA
codec drivers as library. This implements hdac_ext_bus_ops to enable
the reuse of legacy HDA codec drivers with ASoC platform drivers.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
include DAPM Mux and output widgets into the list.
Signed-off-by: Rakesh Ughreja <rakesh.a.ughreja@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
Moved code by function into correct files. Removed dupliction in stream
IRQ handling. Cleaned up init.
Many FIXMEs remain. The biggest is removing the old HDA struct in sdev.
Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
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to wrong branch, close it.

@keyonjiekeyonjie reopened this Jul 23, 2018
We need register/enable irq handler before init_caps, where we are doing
codec probing for HDMI/HDA, otherwise the probing may fail.
We also need to use PCI_IRQ_LEGACY mode at the moment, as PCI_IRQ_MSI
doesn't work for HDMI yet, may need more debug to fix it.
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
plbossart pushed a commit that referenced this pull request Mar 5, 2019
scsi_device_quiesce() and scsi_device_resume() are called during
system-wide suspend and resume. scsi_device_quiesce() only succeeds for
SCSI devices that are in one of the RUNNING, OFFLINE or TRANSPORT_OFFLINE
states (see also scsi_set_device_state()). This patch avoids that the
following warning is triggered when resuming a system for which quiescing a
SCSI device failed:
WARNING: CPU: 2 PID: 11303 at drivers/scsi/scsi_lib.c:2600 scsi_device_resume+0x4f/0x58
CPU: 2 PID: 11303 Comm: kworker/u8:70 Not tainted 5.0.0-rc1+ #50
Hardware name: LENOVO 80E3/Lancer 5B2, BIOS A2CN45WW(V2.13) 08/04/2016
Workqueue: events_unbound async_run_entry_fn
Call Trace:
scsi_dev_type_resume+0x2e/0x60
async_run_entry_fn+0x32/0xd8
process_one_work+0x1f4/0x420
worker_thread+0x28/0x3c0
kthread+0x118/0x130
ret_from_fork+0x22/0x40
Cc: Przemek Socha <soprwa@gmail.com>
Reported-by: Przemek Socha <soprwa@gmail.com>
Fixes: 3a0a529 ("block, scsi: Make SCSI quiesce and resume work reliably") # v4.15
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
bardliao pushed a commit to bardliao/linux that referenced this pull request Apr 26, 2019
scsi_device_quiesce() and scsi_device_resume() are called during
system-wide suspend and resume. scsi_device_quiesce() only succeeds for
SCSI devices that are in one of the RUNNING, OFFLINE or TRANSPORT_OFFLINE
states (see also scsi_set_device_state()). This patch avoids that the
following warning is triggered when resuming a system for which quiescing a
SCSI device failed:
WARNING: CPU: 2 PID: 11303 at drivers/scsi/scsi_lib.c:2600 scsi_device_resume+0x4f/0x58
CPU: 2 PID: 11303 Comm: kworker/u8:70 Not tainted 5.0.0-rc1+ thesofproject#50
Hardware name: LENOVO 80E3/Lancer 5B2, BIOS A2CN45WW(V2.13) 08/04/2016
Workqueue: events_unbound async_run_entry_fn
Call Trace:
scsi_dev_type_resume+0x2e/0x60
async_run_entry_fn+0x32/0xd8
process_one_work+0x1f4/0x420
worker_thread+0x28/0x3c0
kthread+0x118/0x130
ret_from_fork+0x22/0x40
Cc: Przemek Socha <soprwa@gmail.com>
Reported-by: Przemek Socha <soprwa@gmail.com>
Fixes: 3a0a529 ("block, scsi: Make SCSI quiesce and resume work reliably") # v4.15
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
kv2019i pushed a commit that referenced this pull request Jan 26, 2021
…tirq
Commit 39d42fa ("dm crypt: add flags to optionally bypass kcryptd
workqueues") made it possible for some code paths in dm-crypt to be
executed in softirq context, when the underlying driver processes IO
requests in interrupt/softirq context.
When Crypto API backlogs a crypto request, dm-crypt uses
wait_for_completion to avoid sending further requests to an already
overloaded crypto driver. However, if the code is executing in softirq
context, we might get the following stacktrace:
[ 210.235213][ C0] BUG: scheduling while atomic: fio/2602/0x00000102
[ 210.236701][ C0] Modules linked in:
[ 210.237566][ C0] CPU: 0 PID: 2602 Comm: fio Tainted: G W 5.10.0+ #50
[ 210.239292][ C0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
[ 210.241233][ C0] Call Trace:
[ 210.241946][ C0] <IRQ>
[ 210.242561][ C0] dump_stack+0x7d/0xa3
[ 210.243466][ C0] __schedule_bug.cold+0xb3/0xc2
[ 210.244539][ C0] __schedule+0x156f/0x20d0
[ 210.245518][ C0] ? io_schedule_timeout+0x140/0x140
[ 210.246660][ C0] schedule+0xd0/0x270
[ 210.247541][ C0] schedule_timeout+0x1fb/0x280
[ 210.248586][ C0] ? usleep_range+0x150/0x150
[ 210.249624][ C0] ? unpoison_range+0x3a/0x60
[ 210.250632][ C0] ? ____kasan_kmalloc.constprop.0+0x82/0xa0
[ 210.251949][ C0] ? unpoison_range+0x3a/0x60
[ 210.252958][ C0] ? __prepare_to_swait+0xa7/0x190
[ 210.254067][ C0] do_wait_for_common+0x2ab/0x370
[ 210.255158][ C0] ? usleep_range+0x150/0x150
[ 210.256192][ C0] ? bit_wait_io_timeout+0x160/0x160
[ 210.257358][ C0] ? blk_update_request+0x757/0x1150
[ 210.258582][ C0] ? _raw_spin_lock_irq+0x82/0xd0
[ 210.259674][ C0] ? _raw_read_unlock_irqrestore+0x30/0x30
[ 210.260917][ C0] wait_for_completion+0x4c/0x90
[ 210.261971][ C0] crypt_convert+0x19a6/0x4c00
[ 210.263033][ C0] ? _raw_spin_lock_irqsave+0x87/0xe0
[ 210.264193][ C0] ? kasan_set_track+0x1c/0x30
[ 210.265191][ C0] ? crypt_iv_tcw_ctr+0x4a0/0x4a0
[ 210.266283][ C0] ? kmem_cache_free+0x104/0x470
[ 210.267363][ C0] ? crypt_endio+0x91/0x180
[ 210.268327][ C0] kcryptd_crypt_read_convert+0x30e/0x420
[ 210.269565][ C0] blk_update_request+0x757/0x1150
[ 210.270563][ C0] blk_mq_end_request+0x4b/0x480
[ 210.271680][ C0] blk_done_softirq+0x21d/0x340
[ 210.272775][ C0] ? _raw_spin_lock+0x81/0xd0
[ 210.273847][ C0] ? blk_mq_stop_hw_queue+0x30/0x30
[ 210.275031][ C0] ? _raw_read_lock_irq+0x40/0x40
[ 210.276182][ C0] __do_softirq+0x190/0x611
[ 210.277203][ C0] ? handle_edge_irq+0x221/0xb60
[ 210.278340][ C0] asm_call_irq_on_stack+0x12/0x20
[ 210.279514][ C0] </IRQ>
[ 210.280164][ C0] do_softirq_own_stack+0x37/0x40
[ 210.281281][ C0] irq_exit_rcu+0x110/0x1b0
[ 210.282286][ C0] common_interrupt+0x74/0x120
[ 210.283376][ C0] asm_common_interrupt+0x1e/0x40
[ 210.284496][ C0] RIP: 0010:_aesni_enc1+0x65/0xb0
Fix this by making crypt_convert function reentrant from the point of
a single bio and make dm-crypt defer further bio processing to a
workqueue, if Crypto API backlogs a request in interrupt context.
Fixes: 39d42fa ("dm crypt: add flags to optionally bypass kcryptd workqueues")
Cc: stable@vger.kernel.org # v5.9+
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
kv2019i pushed a commit that referenced this pull request Jan 26, 2021
Commit 39d42fa ("dm crypt: add flags to optionally bypass kcryptd
workqueues") made it possible for some code paths in dm-crypt to be
executed in softirq context, when the underlying driver processes IO
requests in interrupt/softirq context.
In this case sometimes when allocating a new crypto request we may get
a stacktrace like below:
[ 210.103008][ C0] BUG: sleeping function called from invalid context at mm/mempool.c:381
[ 210.104746][ C0] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2602, name: fio
[ 210.106599][ C0] CPU: 0 PID: 2602 Comm: fio Tainted: G W 5.10.0+ #50
[ 210.108331][ C0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
[ 210.110212][ C0] Call Trace:
[ 210.110921][ C0] <IRQ>
[ 210.111527][ C0] dump_stack+0x7d/0xa3
[ 210.112411][ C0] ___might_sleep.cold+0x122/0x151
[ 210.113527][ C0] mempool_alloc+0x16b/0x2f0
[ 210.114524][ C0] ? __queue_work+0x515/0xde0
[ 210.115553][ C0] ? mempool_resize+0x700/0x700
[ 210.116586][ C0] ? crypt_endio+0x91/0x180
[ 210.117479][ C0] ? blk_update_request+0x757/0x1150
[ 210.118513][ C0] ? blk_mq_end_request+0x4b/0x480
[ 210.119572][ C0] ? blk_done_softirq+0x21d/0x340
[ 210.120628][ C0] ? __do_softirq+0x190/0x611
[ 210.121626][ C0] crypt_convert+0x29f9/0x4c00
[ 210.122668][ C0] ? _raw_spin_lock_irqsave+0x87/0xe0
[ 210.123824][ C0] ? kasan_set_track+0x1c/0x30
[ 210.124858][ C0] ? crypt_iv_tcw_ctr+0x4a0/0x4a0
[ 210.125930][ C0] ? kmem_cache_free+0x104/0x470
[ 210.126973][ C0] ? crypt_endio+0x91/0x180
[ 210.127947][ C0] kcryptd_crypt_read_convert+0x30e/0x420
[ 210.129165][ C0] blk_update_request+0x757/0x1150
[ 210.130231][ C0] blk_mq_end_request+0x4b/0x480
[ 210.131294][ C0] blk_done_softirq+0x21d/0x340
[ 210.132332][ C0] ? _raw_spin_lock+0x81/0xd0
[ 210.133289][ C0] ? blk_mq_stop_hw_queue+0x30/0x30
[ 210.134399][ C0] ? _raw_read_lock_irq+0x40/0x40
[ 210.135458][ C0] __do_softirq+0x190/0x611
[ 210.136409][ C0] ? handle_edge_irq+0x221/0xb60
[ 210.137447][ C0] asm_call_irq_on_stack+0x12/0x20
[ 210.138507][ C0] </IRQ>
[ 210.139118][ C0] do_softirq_own_stack+0x37/0x40
[ 210.140191][ C0] irq_exit_rcu+0x110/0x1b0
[ 210.141151][ C0] common_interrupt+0x74/0x120
[ 210.142171][ C0] asm_common_interrupt+0x1e/0x40
Fix this by allocating crypto requests with GFP_ATOMIC mask in
interrupt context.
Fixes: 39d42fa ("dm crypt: add flags to optionally bypass kcryptd workqueues")
Cc: stable@vger.kernel.org # v5.9+
Reported-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
aiChaoSONG pushed a commit to aiChaoSONG/linux that referenced this pull request May 6, 2021
Bindings: #include sysctl (some configs need it)
plbossart pushed a commit that referenced this pull request Apr 13, 2022
Problem:
=======
Userspace might read the zero-page instead of actual data from a direct IO
read on a block device if the buffers have been called madvise(MADV_FREE)
on earlier (this is discussed below) due to a race between page reclaim on
MADV_FREE and blkdev direct IO read.
- Race condition:
==============
During page reclaim, the MADV_FREE page check in try_to_unmap_one() checks
if the page is not dirty, then discards its rmap PTE(s) (vs. remap back
if the page is dirty).
However, after try_to_unmap_one() returns to shrink_page_list(), it might
keep the page _anyway_ if page_ref_freeze() fails (it expects exactly
_one_ page reference, from the isolation for page reclaim).
Well, blkdev_direct_IO() gets references for all pages, and on READ
operations it only sets them dirty _later_.
So, if MADV_FREE'd pages (i.e., not dirty) are used as buffers for direct
IO read from block devices, and page reclaim happens during
__blkdev_direct_IO[_simple]() exactly AFTER bio_iov_iter_get_pages()
returns, but BEFORE the pages are set dirty, the situation happens.
The direct IO read eventually completes. Now, when userspace reads the
buffers, the PTE is no longer there and the page fault handler
do_anonymous_page() services that with the zero-page, NOT the data!
A synthetic reproducer is provided.
- Page faults:
===========
If page reclaim happens BEFORE bio_iov_iter_get_pages() the issue doesn't
happen, because that faults-in all pages as writeable, so
do_anonymous_page() sets up a new page/rmap/PTE, and that is used by
direct IO. The userspace reads don't fault as the PTE is there (thus
zero-page is not used/setup).
But if page reclaim happens AFTER it / BEFORE setting pages dirty, the PTE
is no longer there; the subsequent page faults can't help:
The data-read from the block device probably won't generate faults due to
DMA (no MMU) but even in the case it wouldn't use DMA, that happens on
different virtual addresses (not user-mapped addresses) because `struct
bio_vec` stores `struct page` to figure addresses out (which are different
from user-mapped addresses) for the read.
Thus userspace reads (to user-mapped addresses) still fault, then
do_anonymous_page() gets another `struct page` that would address/ map to
other memory than the `struct page` used by `struct bio_vec` for the read.
(The original `struct page` is not available, since it wasn't freed, as
page_ref_freeze() failed due to more page refs. And even if it were
available, its data cannot be trusted anymore.)
Solution:
========
One solution is to check for the expected page reference count in
try_to_unmap_one().
There should be one reference from the isolation (that is also checked in
shrink_page_list() with page_ref_freeze()) plus one or more references
from page mapping(s) (put in discard: label). Further references mean
that rmap/PTE cannot be unmapped/nuked.
(Note: there might be more than one reference from mapping due to
fork()/clone() without CLONE_VM, which use the same `struct page` for
references, until the copy-on-write page gets copied.)
So, additional page references (e.g., from direct IO read) now prevent the
rmap/PTE from being unmapped/dropped; similarly to the page is not freed
per shrink_page_list()/page_ref_freeze()).
- Races and Barriers:
==================
The new check in try_to_unmap_one() should be safe in races with
bio_iov_iter_get_pages() in get_user_pages() fast and slow paths, as it's
done under the PTE lock.
The fast path doesn't take the lock, but it checks if the PTE has changed
and if so, it drops the reference and leaves the page for the slow path
(which does take that lock).
The fast path requires synchronization w/ full memory barrier: it writes
the page reference count first then it reads the PTE later, while
try_to_unmap() writes PTE first then it reads page refcount.
And a second barrier is needed, as the page dirty flag should not be read
before the page reference count (as in __remove_mapping()). (This can be
a load memory barrier only; no writes are involved.)
Call stack/comments:
- try_to_unmap_one()
- page_vma_mapped_walk()
- map_pte() # see pte_offset_map_lock():
pte_offset_map()
spin_lock()
- ptep_get_and_clear()	# write PTE
- smp_mb() # (new barrier) GUP fast path
- page_ref_count() # (new check) read refcount
- page_vma_mapped_walk_done()	# see pte_unmap_unlock():
pte_unmap()
spin_unlock()
- bio_iov_iter_get_pages()
- __bio_iov_iter_get_pages()
- iov_iter_get_pages()
- get_user_pages_fast()
- internal_get_user_pages_fast()
# fast path
- lockless_pages_from_mm()
- gup_{pgd,p4d,pud,pmd,pte}_range()
ptep = pte_offset_map() # not _lock()
pte = ptep_get_lockless(ptep)
page = pte_page(pte)
try_grab_compound_head(page)	# inc refcount
# (RMW/barrier
# on success)
if (pte_val(pte) != pte_val(*ptep)) # read PTE
put_compound_head(page) # dec refcount
# go slow path
# slow path
- __gup_longterm_unlocked()
- get_user_pages_unlocked()
- __get_user_pages_locked()
- __get_user_pages()
- follow_{page,p4d,pud,pmd}_mask()
- follow_page_pte()
ptep = pte_offset_map_lock()
pte = *ptep
page = vm_normal_page(pte)
try_grab_page(page)	# inc refcount
pte_unmap_unlock()
- Huge Pages:
==========
Regarding transparent hugepages, that logic shouldn't change, as MADV_FREE
(aka lazyfree) pages are PageAnon() && !PageSwapBacked()
(madvise_free_pte_range() -> mark_page_lazyfree() -> lru_lazyfree_fn())
thus should reach shrink_page_list() -> split_huge_page_to_list() before
try_to_unmap[_one](), so it deals with normal pages only.
(And in case unlikely/TTU_SPLIT_HUGE_PMD/split_huge_pmd_address() happens,
which should not or be rare, the page refcount should be greater than
mapcount: the head page is referenced by tail pages. That also prevents
checking the head `page` then incorrectly call page_remove_rmap(subpage)
for a tail page, that isn't even in the shrink_page_list()'s page_list (an
effect of split huge pmd/pmvw), as it might happen today in this unlikely
scenario.)
MADV_FREE'd buffers:
===================
So, back to the "if MADV_FREE pages are used as buffers" note. The case
is arguable, and subject to multiple interpretations.
The madvise(2) manual page on the MADV_FREE advice value says:
1) 'After a successful MADV_FREE ... data will be lost when
the kernel frees the pages.'
2) 'the free operation will be canceled if the caller writes
into the page' / 'subsequent writes ... will succeed and
then [the] kernel cannot free those dirtied pages'
3) 'If there is no subsequent write, the kernel can free the
pages at any time.'
Thoughts, questions, considerations... respectively:
1) Since the kernel didn't actually free the page (page_ref_freeze()
failed), should the data not have been lost? (on userspace read.)
2) Should writes performed by the direct IO read be able to cancel
the free operation?
- Should the direct IO read be considered as 'the caller' too,
as it's been requested by 'the caller'?
- Should the bio technique to dirty pages on return to userspace
(bio_check_pages_dirty() is called/used by __blkdev_direct_IO())
be considered in another/special way here?
3) Should an upcoming write from a previously requested direct IO
read be considered as a subsequent write, so the kernel should
not free the pages? (as it's known at the time of page reclaim.)
And lastly:
Technically, the last point would seem a reasonable consideration and
balance, as the madvise(2) manual page apparently (and fairly) seem to
assume that 'writes' are memory access from the userspace process (not
explicitly considering writes from the kernel or its corner cases; again,
fairly).. plus the kernel fix implementation for the corner case of the
largely 'non-atomic write' encompassed by a direct IO read operation, is
relatively simple; and it helps.
Reproducer:
==========
@ test.c (simplified, but works)
#define _GNU_SOURCE
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/mman.h>
int main() {
int fd, i;
char *buf;
fd = open(DEV, O_RDONLY | O_DIRECT);
buf = mmap(NULL, BUF_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
for (i = 0; i < BUF_SIZE; i += PAGE_SIZE)
buf[i] = 1; // init to non-zero
madvise(buf, BUF_SIZE, MADV_FREE);
read(fd, buf, BUF_SIZE);
for (i = 0; i < BUF_SIZE; i += PAGE_SIZE)
printf("%p: 0x%x\n", &buf[i], buf[i]);
return 0;
}
@ block/fops.c (formerly fs/block_dev.c)
+#include <linux/swap.h>
...
... __blkdev_direct_IO[_simple](...)
{
...
+	if (!strcmp(current->comm, "good"))
+ shrink_all_memory(ULONG_MAX);
+
ret = bio_iov_iter_get_pages(...);
+
+	if (!strcmp(current->comm, "bad"))
+ shrink_all_memory(ULONG_MAX);
...
}
@ shell
# NUM_PAGES=4
# PAGE_SIZE=$(getconf PAGE_SIZE)
# yes | dd of=test.img bs=${PAGE_SIZE} count=${NUM_PAGES}
# DEV=$(losetup -f --show test.img)
# gcc -DDEV=\"$DEV\" \
-DBUF_SIZE=$((PAGE_SIZE * NUM_PAGES)) \
-DPAGE_SIZE=${PAGE_SIZE} \
test.c -o test
# od -tx1 $DEV
0000000 79 0a 79 0a 79 0a 79 0a 79 0a 79 0a 79 0a 79 0a
*
0040000
# mv test good
# ./good
0x7f7c10418000: 0x79
0x7f7c10419000: 0x79
0x7f7c1041a000: 0x79
0x7f7c1041b000: 0x79
# mv good bad
# ./bad
0x7fa1b8050000: 0x0
0x7fa1b8051000: 0x0
0x7fa1b8052000: 0x0
0x7fa1b8053000: 0x0
Note: the issue is consistent on v5.17-rc3, but it's intermittent with the
support of MADV_FREE on v4.5 (60%-70% error; needs swap). [wrap
do_direct_IO() in do_blockdev_direct_IO() @ fs/direct-io.c].
- v5.17-rc3:
# for i in {1..1000}; do ./good; done \
| cut -d: -f2 | sort | uniq -c
4000 0x79
# mv good bad
# for i in {1..1000}; do ./bad; done \
| cut -d: -f2 | sort | uniq -c
4000 0x0
# free | grep Swap
Swap: 0 0 0
- v4.5:
# for i in {1..1000}; do ./good; done \
| cut -d: -f2 | sort | uniq -c
4000 0x79
# mv good bad
# for i in {1..1000}; do ./bad; done \
| cut -d: -f2 | sort | uniq -c
2702 0x0
1298 0x79
# swapoff -av
swapoff /swap
# for i in {1..1000}; do ./bad; done \
| cut -d: -f2 | sort | uniq -c
4000 0x79
Ceph/TCMalloc:
=============
For documentation purposes, the use case driving the analysis/fix is Ceph
on Ubuntu 18.04, as the TCMalloc library there still uses MADV_FREE to
release unused memory to the system from the mmap'ed page heap (might be
committed back/used again; it's not munmap'ed.) - PageHeap::DecommitSpan()
-> TCMalloc_SystemRelease() -> madvise() - PageHeap::CommitSpan() ->
TCMalloc_SystemCommit() -> do nothing.
Note: TCMalloc switched back to MADV_DONTNEED a few commits after the
release in Ubuntu 18.04 (google-perftools/gperftools 2.5), so the issue
just 'disappeared' on Ceph on later Ubuntu releases but is still present
in the kernel, and can be hit by other use cases.
The observed issue seems to be the old Ceph bug #22464 [1], where checksum
mismatches are observed (and instrumentation with buffer dumps shows
zero-pages read from mmap'ed/MADV_FREE'd page ranges).
The issue in Ceph was reasonably deemed a kernel bug (comment #50) and
mostly worked around with a retry mechanism, but other parts of Ceph could
still hit that (rocksdb). Anyway, it's less likely to be hit again as
TCMalloc switched out of MADV_FREE by default.
(Some kernel versions/reports from the Ceph bug, and relation with
the MADV_FREE introduction/changes; TCMalloc versions not checked.)
- 4.4 good
- 4.5 (madv_free: introduction)
- 4.9 bad
- 4.10 good? maybe a swapless system
- 4.12 (madv_free: no longer free instantly on swapless systems)
- 4.13 bad
[1] https://tracker.ceph.com/issues/22464
Thanks:
======
Several people contributed to analysis/discussions/tests/reproducers in
the first stages when drilling down on ceph/tcmalloc/linux kernel:
- Dan Hill
- Dan Streetman
- Dongdong Tao
- Gavin Guo
- Gerald Yang
- Heitor Alves de Siqueira
- Ioanna Alifieraki
- Jay Vosburgh
- Matthew Ruffell
- Ponnuvel Palaniyappan
Reviews, suggestions, corrections, comments:
- Minchan Kim
- Yu Zhao
- Huang, Ying
- John Hubbard
- Christoph Hellwig
[mfo@canonical.com: v4]
Link: https://lkml.kernel.org/r/20220209202659.183418-1-mfo@canonical.comLink: https://lkml.kernel.org/r/20220131230255.789059-1-mfo@canonical.com
Fixes: 802a3a9 ("mm: reclaim MADV_FREE pages")
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Dan Hill <daniel.hill@canonical.com>
Cc: Dan Streetman <dan.streetman@canonical.com>
Cc: Dongdong Tao <dongdong.tao@canonical.com>
Cc: Gavin Guo <gavin.guo@canonical.com>
Cc: Gerald Yang <gerald.yang@canonical.com>
Cc: Heitor Alves de Siqueira <halves@canonical.com>
Cc: Ioanna Alifieraki <ioanna-maria.alifieraki@canonical.com>
Cc: Jay Vosburgh <jay.vosburgh@canonical.com>
Cc: Matthew Ruffell <matthew.ruffell@canonical.com>
Cc: Ponnuvel Palaniyappan <ponnuvel.palaniyappan@canonical.com>
Cc: <stable@vger.kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
plbossart pushed a commit that referenced this pull request Jun 16, 2023
The commit 4f7e723 ("cgroup: Fix threadgroup_rwsem <-> cpus_read_lock()
deadlock") fixed the deadlock between cgroup_threadgroup_rwsem and
cpus_read_lock() by introducing cgroup_attach_{lock,unlock}() and removing
cpus_read_{lock,unlock}() from cpuset_attach(). But cgroup_transfer_tasks()
was missed and not handled, which will cause th following warning:
WARNING: CPU: 0 PID: 589 at kernel/cpu.c:526 lockdep_assert_cpus_held+0x32/0x40
CPU: 0 PID: 589 Comm: kworker/1:4 Not tainted 6.4.0-rc2-next-20230517 #50
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Workqueue: events cpuset_hotplug_workfn
RIP: 0010:lockdep_assert_cpus_held+0x32/0x40
<...>
Call Trace:
<TASK>
cpuset_attach+0x40/0x240
cgroup_migrate_execute+0x452/0x5e0
? _raw_spin_unlock_irq+0x28/0x40
cgroup_transfer_tasks+0x1f3/0x360
? find_held_lock+0x32/0x90
? cpuset_hotplug_workfn+0xc81/0xed0
cpuset_hotplug_workfn+0xcb1/0xed0
? process_one_work+0x248/0x5b0
process_one_work+0x2b9/0x5b0
worker_thread+0x56/0x3b0
? process_one_work+0x5b0/0x5b0
kthread+0xf1/0x120
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x1f/0x30
</TASK>
So just use the cgroup_attach_{lock,unlock}() helper to fix it.
Reported-by: Zhao Gongyi <zhaogongyi@bytedance.com>
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Fixes: 05c7b7a ("cgroup/cpuset: Fix a race between cpuset_attach() and cpu hotplug")
Cc: stable@vger.kernel.org # v5.17+
Signed-off-by: Tejun Heo <tj@kernel.org>
wenliangwu pushed a commit that referenced this pull request Oct 30, 2023
Commit a1d7671 ("md: use mddev->external to select holder in
export_rdev()") fix the problem that 'claim_rdev' is used for
blkdev_get_by_dev() while 'rdev' is used for blkdev_put().
However, if mddev->external is changed from 0 to 1, then 'rdev' is used
for blkdev_get_by_dev() while 'claim_rdev' is used for blkdev_put(). And
this problem can be reporduced reliably by following:
New file: mdadm/tests/23rdev-lifetime
devname=${dev0##*/}
devt=`cat /sys/block/$devname/dev`
pid=""
runtime=2
clean_up_test() {
pill -9 $pid
echo clear > /sys/block/md0/md/array_state
}
trap 'clean_up_test' EXIT
add_by_sysfs() {
while true; do
echo $devt > /sys/block/md0/md/new_dev
done
}
remove_by_sysfs(){
while true; do
echo remove > /sys/block/md0/md/dev-${devname}/state
done
}
echo md0 > /sys/module/md_mod/parameters/new_array || die "create md0 failed"
add_by_sysfs &
pid="$pid $!"
remove_by_sysfs &
pid="$pid $!"
sleep $runtime
exit 0
Test cmd:
./test --save-logs --logdir=/tmp/ --keep-going --dev=loop --tests=23rdev-lifetime
Test result:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 960 at block/bdev.c:618 blkdev_put+0x27c/0x330
Modules linked in: multipath md_mod loop
CPU: 0 PID: 960 Comm: test Not tainted 6.5.0-rc2-00121-g01e55c376936-dirty #50
RIP: 0010:blkdev_put+0x27c/0x330
Call Trace:
<TASK>
export_rdev.isra.23+0x50/0xa0 [md_mod]
mddev_unlock+0x19d/0x300 [md_mod]
rdev_attr_store+0xec/0x190 [md_mod]
sysfs_kf_write+0x52/0x70
kernfs_fop_write_iter+0x19a/0x2a0
vfs_write+0x3b5/0x770
ksys_write+0x74/0x150
__x64_sys_write+0x22/0x30
do_syscall_64+0x40/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fix the problem by recording if 'rdev' is used as holder.
Fixes: a1d7671 ("md: use mddev->external to select holder in export_rdev()")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230825025532.1523008-3-yukuai1@huaweicloud.com
oder-chiou pushed a commit to oder-chiou/linux-soundwire that referenced this pull request May 5, 2026
An out of bounds write happens when setting the default power state.
KASAN sees this as:
[drm] radeon: 512M of GTT memory ready.
[drm] GART: num cpu pages 131072, num gpu pages 131072
==================================================================
BUG: KASAN: slab-out-of-bounds in
radeon_atombios_parse_power_table_1_3+0x1837/0x1998 [radeon]
Write of size 4 at addr ffff88810178d858 by task systemd-udevd/157
CPU: 0 PID: 157 Comm: systemd-udevd Not tainted 5.12.0-E620 thesofproject#50
Hardware name: eMachines eMachines E620 /Nile , BIOS V1.03 09/30/2008
Call Trace:
dump_stack+0xa5/0xe6
print_address_description.constprop.0+0x18/0x239
kasan_report+0x170/0x1a8
radeon_atombios_parse_power_table_1_3+0x1837/0x1998 [radeon]
radeon_atombios_get_power_modes+0x144/0x1888 [radeon]
radeon_pm_init+0x1019/0x1904 [radeon]
rs690_init+0x76e/0x84a [radeon]
radeon_device_init+0x1c1a/0x21e5 [radeon]
radeon_driver_load_kms+0xf5/0x30b [radeon]
drm_dev_register+0x255/0x4a0 [drm]
radeon_pci_probe+0x246/0x2f6 [radeon]
pci_device_probe+0x1aa/0x294
really_probe+0x30e/0x850
driver_probe_device+0xe6/0x135
device_driver_attach+0xc1/0xf8
__driver_attach+0x13f/0x146
bus_for_each_dev+0xfa/0x146
bus_add_driver+0x2b3/0x447
driver_register+0x242/0x2c1
do_one_initcall+0x149/0x2fd
do_init_module+0x1ae/0x573
load_module+0x4dee/0x5cca
__do_sys_finit_module+0xf1/0x140
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xae
Without KASAN, this will manifest later when the kernel attempts to
allocate memory that was stomped, since it collides with the inline slab
freelist pointer:
invalid opcode: 0000 [thesofproject#1] SMP NOPTI
CPU: 0 PID: 781 Comm: openrc-run.sh Tainted: G W 5.10.12-gentoo-E620 thesofproject#2
Hardware name: eMachines eMachines E620 /Nile , BIOS V1.03 09/30/2008
RIP: 0010:kfree+0x115/0x230
Code: 89 c5 e8 75 ea ff ff 48 8b 00 0f ba e0 09 72 63 e8 1f f4 ff ff 41 89 c4 48 8b 45 00 0f ba e0 10 72 0a 48 8b 45 08 a8 01 75 02 <0f> 0b 44 89 e1 48 c7 c2 00 f0 ff ff be 06 00 00 00 48 d3 e2 48 c7
RSP: 0018:ffffb42f40267e10 EFLAGS: 00010246
RAX: ffffd61280ee8d88 RBX: 0000000000000004 RCX: 000000008010000d
RDX: 4000000000000000 RSI: ffffffffba1360b0 RDI: ffffd61280ee8d80
RBP: ffffd61280ee8d80 R08: ffffffffb91bebdf R09: 0000000000000000
R10: ffff8fe2c1047ac8 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000100
FS: 00007fe80eff6b68(0000) GS:ffff8fe339c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe80eec7bc0 CR3: 0000000038012000 CR4: 00000000000006f0
Call Trace:
__free_fdtable+0x16/0x1f
put_files_struct+0x81/0x9b
do_exit+0x433/0x94d
do_group_exit+0xa6/0xa6
__x64_sys_exit_group+0xf/0xf
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fe80ef64bea
Code: Unable to access opcode bytes at RIP 0x7fe80ef64bc0.
RSP: 002b:00007ffdb1c47528 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fe80ef64bea
RDX: 00007fe80ef64f60 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 00007fe80ee2c620 R11: 0000000000000246 R12: 00007fe80eff41e0
R13: 00000000ffffffff R14: 0000000000000024 R15: 00007fe80edf9cd0
Modules linked in: radeon(+) ath5k(+) snd_hda_codec_realtek ...
Use a valid power_state index when initializing the "flags" and "misc"
and "misc2" fields.
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=211537
Reported-by: Erhard F. <erhard_f@mailbox.org>
Fixes: a48b9b4 ("drm/radeon/kms/pm: add asic specific callbacks for getting power state (v2)")
Fixes: 79daedc ("drm/radeon/kms: minor pm cleanups")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
oder-chiou pushed a commit to oder-chiou/linux-soundwire that referenced this pull request May 5, 2026
oder-chiou pushed a commit to oder-chiou/linux-soundwire that referenced this pull request May 5, 2026
Fix suspicious rcu_dereference_protected() usage when offloading tc action.
We should hold tcfa_lock to offload tc action in action initiation.
Without these changes, the following warning will be observed:
WARNING: suspicious RCU usage
5.16.0-rc5-net-next-01504-g7d1f236dcffa-dirty thesofproject#50 Tainted: G I
-----------------------------
include/net/tc_act/tc_tunnel_key.h:33 suspicious rcu_dereference_protected() usage!
1 lock held by tc/12108:
CPU: 4 PID: 12108 Comm: tc Tainted: G
Hardware name: Dell Inc. PowerEdge R740/07WCGN, BIOS 1.6.11 11/20/2018
Call Trace:
<TASK>
dump_stack_lvl+0x49/0x5e
dump_stack+0x10/0x12
lockdep_rcu_suspicious+0xed/0xf8
tcf_tunnel_key_offload_act_setup+0x1de/0x300 [act_tunnel_key]
tcf_action_offload_add_ex+0xc0/0x1f0
tcf_action_init+0x26a/0x2f0
tcf_action_add+0xa9/0x1f0
tc_ctl_action+0xfb/0x170
rtnetlink_rcv_msg+0x169/0x510
? sched_clock+0x9/0x10
? rtnl_newlink+0x70/0x70
netlink_rcv_skb+0x55/0x100
rtnetlink_rcv+0x15/0x20
netlink_unicast+0x1a8/0x270
netlink_sendmsg+0x245/0x490
sock_sendmsg+0x65/0x70
____sys_sendmsg+0x219/0x260
? __import_iovec+0x2c/0x150
___sys_sendmsg+0xb7/0x100
? __lock_acquire+0x3d5/0x1f40
? __this_cpu_preempt_check+0x13/0x20
? lock_is_held_type+0xe4/0x140
? sched_clock+0x9/0x10
? ktime_get_coarse_real_ts64+0xbe/0xd0
? __this_cpu_preempt_check+0x13/0x20
? lockdep_hardirqs_on+0x7e/0x100
? ktime_get_coarse_real_ts64+0xbe/0xd0
? trace_hardirqs_on+0x2a/0xf0
__sys_sendmsg+0x5a/0xa0
? syscall_trace_enter.constprop.0+0x1dd/0x220
__x64_sys_sendmsg+0x1f/0x30
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f4db7bb7a60
Fixes: 8cbfe93 ("flow_offload: allow user to offload tc action to net device")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
oder-chiou pushed a commit to oder-chiou/linux-soundwire that referenced this pull request May 5, 2026
…not present
DG1/DG2 and MTL+ has added a new display-present HW flag. Check this
flag and if cleared, disable the driver's display functionality.
So far the missing check resulted in running the display initialization
sequence, and the WARNs below, due to the display register accesses
timing out:
[ 3.902843] ------------[ cut here ]------------
[ 3.902848] i915 0000:03:00.0: drm_WARN_ON(intel_de_wait_for_set(dev_priv, ((const i915_reg_t){ .reg = (0x42000) }), (1 << (27 - (pg))), 1))
[ 3.902879] WARNING: CPU: 6 PID: 462 at drivers/gpu/drm/i915/display/intel_display_power_well.c:326 gen9_wait_for_power_well_fuses+0x71/0x80 [i915]
[ 3.903009] Modules linked in: hid_sensor_hub intel_ishtp_hid i915(+) rtsx_pci_sdmmc drm_buddy mmc_core drm_display_helper crct10dif_pclmul nvme cec crc32_pclmul intel_ish_ipc crc32c_intel ucsi_acpi hid_multitouch nvme_core ghash_clmulni_intel typec_ucsi rtsx_pci ttm sha512_ssse3 serio_raw intel_ishtp typec video i2c_hid_acpi i2c_hid wmi pinctrl_tigerlake ip6_tables ip_tables x_tables fuse
[ 3.903021] CPU: 6 PID: 462 Comm: systemd-udevd Tainted: G U 6.2.0-rc6+ thesofproject#50
[ 3.903023] Hardware name: LENOVO 82VB/LNVNB161216, BIOS KMCN09WW 04/26/2022
[ 3.903023] RIP: 0010:gen9_wait_for_power_well_fuses+0x71/0x80 [i915]
[ 3.903105] Code: 48 8b 5f 50 48 85 db 75 03 48 8b 1f e8 98 bb 0d e9 48 c7 c1 00 65 a1 c0 48 89 da 48 c7 c7 4b c5 a3 c0 48 89 c6 e8 e3 df 53 e9 <0f> 0b 5b c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90
[ 3.903106] RSP: 0018:ffffa7cec0b07a98 EFLAGS: 0001029
[ 3.903107] RAX: 0000000000000080 RBX: ffff9a05430eaaa0 RCX: 0000000000000000
[ 3.903108] RDX: 0000000000000001 RSI: ffffffffaa7ab69e RDI: 00000000ffffffff
[ 3.903108] RBP: ffff9a0552ba2020 R08: ffffffffab062ce0 R09: 00000000abd3ffc2
[ 3.903109] R10: ffffffffffffffff R11: 0000000000000081 R12: 0000000000000000
[ 3.903109] R13: ffff9a05532a9cb0 R14: ffffffffc09e1670 R15: ffff9a0543132000
[ 3.903110] FS: 00007f24d0fe5b40(0000) GS:ffff9a0ccf780000(0000) knlGS:0000000000000000
[ 3.903110] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3.903111] CR2: 00005643d7a31a28 CR3: 0000000111614002 CR4: 0000000000770ee0
[ 3.903112] PKRU: 55555554
[ 3.903112] Call Trace:
[ 3.903113] <TASK>
[ 3.903114] hsw_power_well_enable+0x12f/0x1a0 [i915]
[ 3.903191] intel_power_well_enable+0x21/0x70 [i915]
[ 3.903265] icl_display_core_init+0x92/0x6a0 [i915]
[ 3.903346] intel_power_domains_init_hw+0x1da/0x5b0 [i915]
[ 3.903422] intel_modeset_init_noirq+0x60/0x250 [i915]
[ 3.903497] i915_driver_probe+0x562/0xe10 [i915]
[ 3.903557] ? i915_pci_probe+0x87/0x180 [i915]
[ 3.903617] local_pci_probe+0x3e/0x80
[ 3.903621] pci_device_probe+0xb3/0x210
[ 3.903622] really_probe+0xdb/0x380
[ 3.903624] ? pm_runtime_barrier+0x50/0x90
[ 3.903626] __driver_probe_device+0x78/0x170
[ 3.903627] driver_probe_device+0x1f/0x90
[ 3.903628] __driver_attach+0xce/0x1c0
[ 3.903629] ? __pfx___driver_attach+0x10/0x10
[ 3.903630] bus_for_each_dev+0x5f/0x90
[ 3.903631] bus_add_driver+0x1ae/0x200
[ 3.903632] driver_register+0x89/0xe0
[ 3.903634] i915_init+0x1f/0x7f [i915]
[ 3.903695] ? __pfx_init_module+0x10/0x10 [i915]
[ 3.903751] do_one_initcall+0x43/0x220
[ 3.903753] ? kmalloc_trace+0x26/0x90
[ 3.903756] do_init_module+0x4a/0x200
[ 3.903758] __do_sys_init_module+0x157/0x180
[ 3.903760] do_syscall_64+0x58/0xc0
[ 3.903762] ? do_syscall_64+0x67/0xc0
[ 3.903762] ? exc_page_fault+0x70/0x170
[ 3.903764] entry_SYSCALL_64_after_hwframe+0x72/0xdc
Bspec: 49189, 53112
v2: (Jani)
- Change "Display fused off" dmesg info to "Display not present".
- Zero only runtime->pipe_mask, other fields being zeroed based on this
later.
- Detect display presence already before the fused-off checks and only for
HAS_DISPLAY().
v3: Fix "preset" vs "present" typo.
Reported-and-tested-by: iczero <iczero@hellomouse.net>
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/8015
Cc: iczero <iczero@hellomouse.net>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230208114300.3123934-4-imre.deak@intel.com
oder-chiou pushed a commit to oder-chiou/linux-soundwire that referenced this pull request May 5, 2026
No need to print out the table - users won't really be able
to tell much from it anyway and the messages around this
erratum are unnecessarily obtuse.
Instead clearly inform the user that a 256 kB hole is being
punched in their memory map at the 1.75 GB physical address.
Not that there are many PPro users left. :-)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: H . Peter Anvin <hpa@zytor.com>
Cc: Andy Shevchenko <andy@kernel.org>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Paul Menzel <pmenzel@molgen.mpg.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://patch.msgid.link/20250515120549.2820541-4-mingo@kernel.org
ujfalusi pushed a commit to ujfalusi/sof-linux that referenced this pull request Jul 29, 2026
Introduce support for `zerocopy` [1][2]:
Fast, safe, compile error. Pick two.
Zerocopy makes zero-cost memory manipulation effortless. We write
`unsafe` so you don't have to.
It essentially provides derivable traits (e.g. `FromBytes`) and macros
(e.g. `transmute!`) for safely converting between byte sequences and
other types. Having such support allows us to remove some `unsafe` code.
It is among the most downloaded Rust crates (top thesofproject#50 recent, top thesofproject#100
all-time downloads; according to crates.io), and it is also used by the
Rust compiler itself.
The series starts with a few preparation commits, then the `zerocopy`
and `zerocopy-derive` crates are added. Finally, an example patch using
it is on top, removing one `unsafe impl`.
I had to adapt the crates slightly (just +2/-3 lines), but both patches
could potentially be provided upstream eventually. Please see the
commits for details.
In total, it is about ~39k lines added, ~32k without counting `benches/`
which are just for documentation purposes.
See the cover letter for `syn` for some more details about depending on
third-party crates in commit 54e3eae ("Merge patch series "`syn`
support"").
The codegen of an isolated example function similar to the patch on top
is essentially identical. It also turns out that (for that particular
case) `zerocopy`'s version, even under `debug-assertions` enabled, has
no remaining panics, unlike a few in the current code (because the
compiler can prove the remaining `ub_checks` statically).
So their "fast, safe" does indeed check out -- at least in that case.
P.S. This version of `zerocopy` has already the unstable `Ptr{,Inner}`
types -- to play with them, please use:
make ... KRUSTFLAGS=--cfg=zerocopy_unstable_ptr
Link: https://github.com/google/zerocopy [1]
Link: https://docs.rs/zerocopy [2]
Link: https://patch.msgid.link/20260608141439.182634-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
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