<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/drivers/base/core.c, branch v5.15-rc2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge branch 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb</title>
<updated>2021-09-03T17:34:44+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-09-03T17:34:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3de18c865f504ab59ed2588b1e11acd4bcb9ea09'/>
<id>3de18c865f504ab59ed2588b1e11acd4bcb9ea09</id>
<content type='text'>
Pull swiotlb updates from Konrad Rzeszutek Wilk:
 "A new feature called restricted DMA pools. It allows SWIOTLB to
  utilize per-device (or per-platform) allocated memory pools instead of
  using the global one.

  The first big user of this is ARM Confidential Computing where the
  memory for DMA operations can be set per platform"

* 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: (23 commits)
  swiotlb: use depends on for DMA_RESTRICTED_POOL
  of: restricted dma: Don't fail device probe on rmem init failure
  of: Move of_dma_set_restricted_buffer() into device.c
  powerpc/svm: Don't issue ultracalls if !mem_encrypt_active()
  s390/pv: fix the forcing of the swiotlb
  swiotlb: Free tbl memory in swiotlb_exit()
  swiotlb: Emit diagnostic in swiotlb_exit()
  swiotlb: Convert io_default_tlb_mem to static allocation
  of: Return success from of_dma_set_restricted_buffer() when !OF_ADDRESS
  swiotlb: add overflow checks to swiotlb_bounce
  swiotlb: fix implicit debugfs declarations
  of: Add plumbing for restricted DMA pool
  dt-bindings: of: Add restricted DMA pool
  swiotlb: Add restricted DMA pool initialization
  swiotlb: Add restricted DMA alloc/free support
  swiotlb: Refactor swiotlb_tbl_unmap_single
  swiotlb: Move alloc_size to swiotlb_find_slots
  swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull swiotlb updates from Konrad Rzeszutek Wilk:
 "A new feature called restricted DMA pools. It allows SWIOTLB to
  utilize per-device (or per-platform) allocated memory pools instead of
  using the global one.

  The first big user of this is ARM Confidential Computing where the
  memory for DMA operations can be set per platform"

* 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: (23 commits)
  swiotlb: use depends on for DMA_RESTRICTED_POOL
  of: restricted dma: Don't fail device probe on rmem init failure
  of: Move of_dma_set_restricted_buffer() into device.c
  powerpc/svm: Don't issue ultracalls if !mem_encrypt_active()
  s390/pv: fix the forcing of the swiotlb
  swiotlb: Free tbl memory in swiotlb_exit()
  swiotlb: Emit diagnostic in swiotlb_exit()
  swiotlb: Convert io_default_tlb_mem to static allocation
  of: Return success from of_dma_set_restricted_buffer() when !OF_ADDRESS
  swiotlb: add overflow checks to swiotlb_bounce
  swiotlb: fix implicit debugfs declarations
  of: Add plumbing for restricted DMA pool
  dt-bindings: of: Add restricted DMA pool
  swiotlb: Add restricted DMA pool initialization
  swiotlb: Add restricted DMA alloc/free support
  swiotlb: Refactor swiotlb_tbl_unmap_single
  swiotlb: Move alloc_size to swiotlb_find_slots
  swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing
  swiotlb: Update is_swiotlb_active to add a struct device argument
  swiotlb: Update is_swiotlb_buffer to add a struct device argument
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi</title>
<updated>2021-09-02T22:09:46+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-09-02T22:09:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a9c9a6f741cdaa2fa9ba24a790db8d07295761e3'/>
<id>a9c9a6f741cdaa2fa9ba24a790db8d07295761e3</id>
<content type='text'>
Pull SCSI updates from James Bottomley:
 "This series consists of the usual driver updates (ufs, qla2xxx,
  target, smartpqi, lpfc, mpt3sas).

  The core change causing the most churn was replacing the command
  request field request with a macro, allowing us to offset map to it
  and remove the redundant field; the same was also done for the tag
  field.

  The most impactful change is the final removal of scsi_ioctl, which
  has been deprecated for over a decade"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (293 commits)
  scsi: ufs: Fix ufshcd_request_sense_async() for Samsung KLUFG8RHDA-B2D1
  scsi: ufs: ufs-exynos: Fix static checker warning
  scsi: mpt3sas: Use the proper SCSI midlayer interfaces for PI
  scsi: lpfc: Use the proper SCSI midlayer interfaces for PI
  scsi: lpfc: Copyright updates for 14.0.0.1 patches
  scsi: lpfc: Update lpfc version to 14.0.0.1
  scsi: lpfc: Add bsg support for retrieving adapter cmf data
  scsi: lpfc: Add cmf_info sysfs entry
  scsi: lpfc: Add debugfs support for cm framework buffers
  scsi: lpfc: Add support for maintaining the cm statistics buffer
  scsi: lpfc: Add rx monitoring statistics
  scsi: lpfc: Add support for the CM framework
  scsi: lpfc: Add cmfsync WQE support
  scsi: lpfc: Add support for cm enablement buffer
  scsi: lpfc: Add cm statistics buffer support
  scsi: lpfc: Add EDC ELS support
  scsi: lpfc: Expand FPIN and RDF receive logging
  scsi: lpfc: Add MIB feature enablement support
  scsi: lpfc: Add SET_HOST_DATA mbox cmd to pass date/time info to firmware
  scsi: fc: Add EDC ELS definition
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull SCSI updates from James Bottomley:
 "This series consists of the usual driver updates (ufs, qla2xxx,
  target, smartpqi, lpfc, mpt3sas).

  The core change causing the most churn was replacing the command
  request field request with a macro, allowing us to offset map to it
  and remove the redundant field; the same was also done for the tag
  field.

  The most impactful change is the final removal of scsi_ioctl, which
  has been deprecated for over a decade"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (293 commits)
  scsi: ufs: Fix ufshcd_request_sense_async() for Samsung KLUFG8RHDA-B2D1
  scsi: ufs: ufs-exynos: Fix static checker warning
  scsi: mpt3sas: Use the proper SCSI midlayer interfaces for PI
  scsi: lpfc: Use the proper SCSI midlayer interfaces for PI
  scsi: lpfc: Copyright updates for 14.0.0.1 patches
  scsi: lpfc: Update lpfc version to 14.0.0.1
  scsi: lpfc: Add bsg support for retrieving adapter cmf data
  scsi: lpfc: Add cmf_info sysfs entry
  scsi: lpfc: Add debugfs support for cm framework buffers
  scsi: lpfc: Add support for maintaining the cm statistics buffer
  scsi: lpfc: Add rx monitoring statistics
  scsi: lpfc: Add support for the CM framework
  scsi: lpfc: Add cmfsync WQE support
  scsi: lpfc: Add support for cm enablement buffer
  scsi: lpfc: Add cm statistics buffer support
  scsi: lpfc: Add EDC ELS support
  scsi: lpfc: Expand FPIN and RDF receive logging
  scsi: lpfc: Add MIB feature enablement support
  scsi: lpfc: Add SET_HOST_DATA mbox cmd to pass date/time info to firmware
  scsi: fc: Add EDC ELS definition
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'printk-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux</title>
<updated>2021-09-02T01:41:13+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-09-02T01:41:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=df43d903828c59afb9e93b59835127a02e1f8144'/>
<id>df43d903828c59afb9e93b59835127a02e1f8144</id>
<content type='text'>
Pull printk updates from Petr Mladek:

 - Optionally, provide an index of possible printk messages via
   &lt;debugfs&gt;/printk/index/. It can be used when monitoring important
   kernel messages on a farm of various hosts. The monitor has to be
   updated when some messages has changed or are not longer available by
   a newly deployed kernel.

 - Add printk.console_no_auto_verbose boot parameter. It allows to
   generate crash dump even with slow consoles in a reasonable time
   frame.

 - Remove printk_safe buffers. The messages are always stored directly
   to the main logbuffer, even in NMI or recursive context. Also it
   allows to serialize syslog operations by a mutex instead of a spin
   lock.

 - Misc clean up and build fixes.

* tag 'printk-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk/index: Fix -Wunused-function warning
  lib/nmi_backtrace: Serialize even messages about idle CPUs
  printk: Add printk.console_no_auto_verbose boot parameter
  printk: Remove console_silent()
  lib/test_scanf: Handle n_bits == 0 in random tests
  printk: syslog: close window between wait and read
  printk: convert @syslog_lock to mutex
  printk: remove NMI tracking
  printk: remove safe buffers
  printk: track/limit recursion
  lib/nmi_backtrace: explicitly serialize banner and regs
  printk: Move the printk() kerneldoc comment to its new home
  printk/index: Fix warning about missing prototypes
  MIPS/asm/printk: Fix build failure caused by printk
  printk: index: Add indexing support to dev_printk
  printk: Userspace format indexing support
  printk: Rework parse_prefix into printk_parse_prefix
  printk: Straighten out log_flags into printk_info_flags
  string_helpers: Escape double quotes in escape_special
  printk/console: Check consistent sequence number when handling race in console_unlock()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull printk updates from Petr Mladek:

 - Optionally, provide an index of possible printk messages via
   &lt;debugfs&gt;/printk/index/. It can be used when monitoring important
   kernel messages on a farm of various hosts. The monitor has to be
   updated when some messages has changed or are not longer available by
   a newly deployed kernel.

 - Add printk.console_no_auto_verbose boot parameter. It allows to
   generate crash dump even with slow consoles in a reasonable time
   frame.

 - Remove printk_safe buffers. The messages are always stored directly
   to the main logbuffer, even in NMI or recursive context. Also it
   allows to serialize syslog operations by a mutex instead of a spin
   lock.

 - Misc clean up and build fixes.

* tag 'printk-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk/index: Fix -Wunused-function warning
  lib/nmi_backtrace: Serialize even messages about idle CPUs
  printk: Add printk.console_no_auto_verbose boot parameter
  printk: Remove console_silent()
  lib/test_scanf: Handle n_bits == 0 in random tests
  printk: syslog: close window between wait and read
  printk: convert @syslog_lock to mutex
  printk: remove NMI tracking
  printk: remove safe buffers
  printk: track/limit recursion
  lib/nmi_backtrace: explicitly serialize banner and regs
  printk: Move the printk() kerneldoc comment to its new home
  printk/index: Fix warning about missing prototypes
  MIPS/asm/printk: Fix build failure caused by printk
  printk: index: Add indexing support to dev_printk
  printk: Userspace format indexing support
  printk: Rework parse_prefix into printk_parse_prefix
  printk: Straighten out log_flags into printk_info_flags
  string_helpers: Escape double quotes in escape_special
  printk/console: Check consistent sequence number when handling race in console_unlock()
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branches 'acpi-numa', 'acpi-glue', 'acpi-config' and 'acpi-pmic'</title>
<updated>2021-08-30T17:30:37+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-08-30T17:30:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7c85154643df00f19db43c49dfef23b8fa93f0c9'/>
<id>7c85154643df00f19db43c49dfef23b8fa93f0c9</id>
<content type='text'>
* acpi-numa:
  ACPI: Add LoongArch support for ACPI_PROCESSOR/ACPI_NUMA

* acpi-glue:
  driver core: Split device_platform_notify()
  software nodes: Split software_node_notify()
  ACPI: glue: Eliminate acpi_platform_notify()
  ACPI: bus: Rename functions to avoid name collision
  ACPI: glue: Change return type of two functions to void
  ACPI: glue: Rearrange acpi_device_notify()

* acpi-config:
  ACPI: configfs: Make get_header() to return error pointer
  ACPI: configfs: Use sysfs_emit() in "show" functions

* acpi-pmic:
  ACPI / PMIC: XPower: optimize MIPI PMIQ sequence I2C-bus accesses
  ACPI / PMIC: XPower: optimize I2C-bus accesses
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* acpi-numa:
  ACPI: Add LoongArch support for ACPI_PROCESSOR/ACPI_NUMA

* acpi-glue:
  driver core: Split device_platform_notify()
  software nodes: Split software_node_notify()
  ACPI: glue: Eliminate acpi_platform_notify()
  ACPI: bus: Rename functions to avoid name collision
  ACPI: glue: Change return type of two functions to void
  ACPI: glue: Rearrange acpi_device_notify()

* acpi-config:
  ACPI: configfs: Make get_header() to return error pointer
  ACPI: configfs: Use sysfs_emit() in "show" functions

* acpi-pmic:
  ACPI / PMIC: XPower: optimize MIPI PMIQ sequence I2C-bus accesses
  ACPI / PMIC: XPower: optimize I2C-bus accesses
</pre>
</div>
</content>
</entry>
<entry>
<title>PCI/MSI: Protect msi_desc::masked for multi-MSI</title>
<updated>2021-08-10T08:59:20+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2021-07-29T21:51:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=77e89afc25f30abd56e76a809ee2884d7c1b63ce'/>
<id>77e89afc25f30abd56e76a809ee2884d7c1b63ce</id>
<content type='text'>
Multi-MSI uses a single MSI descriptor and there is a single mask register
when the device supports per vector masking. To avoid reading back the mask
register the value is cached in the MSI descriptor and updates are done by
clearing and setting bits in the cache and writing it to the device.

But nothing protects msi_desc::masked and the mask register from being
modified concurrently on two different CPUs for two different Linux
interrupts which belong to the same multi-MSI descriptor.

Add a lock to struct device and protect any operation on the mask and the
mask register with it.

This makes the update of msi_desc::masked unconditional, but there is no
place which requires a modification of the hardware register without
updating the masked cache.

msi_mask_irq() is now an empty wrapper which will be cleaned up in follow
up changes.

The problem goes way back to the initial support of multi-MSI, but picking
the commit which introduced the mask cache is a valid cut off point
(2.6.30).

Fixes: f2440d9acbe8 ("PCI MSI: Refactor interrupt masking code")
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Tested-by: Marc Zyngier &lt;maz@kernel.org&gt;
Reviewed-by: Marc Zyngier &lt;maz@kernel.org&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210729222542.726833414@linutronix.de

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Multi-MSI uses a single MSI descriptor and there is a single mask register
when the device supports per vector masking. To avoid reading back the mask
register the value is cached in the MSI descriptor and updates are done by
clearing and setting bits in the cache and writing it to the device.

But nothing protects msi_desc::masked and the mask register from being
modified concurrently on two different CPUs for two different Linux
interrupts which belong to the same multi-MSI descriptor.

Add a lock to struct device and protect any operation on the mask and the
mask register with it.

This makes the update of msi_desc::masked unconditional, but there is no
place which requires a modification of the hardware register without
updating the masked cache.

msi_mask_irq() is now an empty wrapper which will be cleaned up in follow
up changes.

The problem goes way back to the initial support of multi-MSI, but picking
the commit which introduced the mask cache is a valid cut off point
(2.6.30).

Fixes: f2440d9acbe8 ("PCI MSI: Refactor interrupt masking code")
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Tested-by: Marc Zyngier &lt;maz@kernel.org&gt;
Reviewed-by: Marc Zyngier &lt;maz@kernel.org&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210729222542.726833414@linutronix.de

</pre>
</div>
</content>
</entry>
<entry>
<title>scsi: ufshcd: Fix device links when BOOT WLUN fails to probe</title>
<updated>2021-08-10T03:19:26+00:00</updated>
<author>
<name>Adrian Hunter</name>
<email>adrian.hunter@intel.com</email>
</author>
<published>2021-08-06T13:04:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=bf25967ac54129ffb676ee0dbe3b8b34af6c6232'/>
<id>bf25967ac54129ffb676ee0dbe3b8b34af6c6232</id>
<content type='text'>
Managed device links are deleted by device_del(). However it is possible to
add a device link to a consumer before device_add(), and then discovering
an error prevents the device from being used. In that case normally
references to the device would be dropped and the device would be deleted.
However the device link holds a reference to the device, so the device link
and device remain indefinitely (unless the supplier is deleted).

For UFSHCD, if a LUN fails to probe (e.g. absent BOOT WLUN), the device
will not have been registered but can still have a device link holding a
reference to the device. The unwanted device link will prevent runtime
suspend indefinitely.

Amend device link removal to accept removal of a link with an unregistered
consumer device (suggested by Rafael), and fix UFSHCD by explicitly
deleting the device link when SCSI destroys the SCSI device.

Link: https://lore.kernel.org/r/a1c9bac8-b560-b662-f0aa-58c7e000cbbd@intel.com
Fixes: b294ff3e3449 ("scsi: ufs: core: Enable power management for wlun")
Reviewed-by: Rafael J. Wysocki &lt;rafael@kernel.org&gt;
Signed-off-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Managed device links are deleted by device_del(). However it is possible to
add a device link to a consumer before device_add(), and then discovering
an error prevents the device from being used. In that case normally
references to the device would be dropped and the device would be deleted.
However the device link holds a reference to the device, so the device link
and device remain indefinitely (unless the supplier is deleted).

For UFSHCD, if a LUN fails to probe (e.g. absent BOOT WLUN), the device
will not have been registered but can still have a device link holding a
reference to the device. The unwanted device link will prevent runtime
suspend indefinitely.

Amend device link removal to accept removal of a link with an unregistered
consumer device (suggested by Rafael), and fix UFSHCD by explicitly
deleting the device link when SCSI destroys the SCSI device.

Link: https://lore.kernel.org/r/a1c9bac8-b560-b662-f0aa-58c7e000cbbd@intel.com
Fixes: b294ff3e3449 ("scsi: ufs: core: Enable power management for wlun")
Reviewed-by: Rafael J. Wysocki &lt;rafael@kernel.org&gt;
Signed-off-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>swiotlb: Convert io_default_tlb_mem to static allocation</title>
<updated>2021-07-24T00:14:43+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will@kernel.org</email>
</author>
<published>2021-07-20T13:38:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=463e862ac63ef27fca423782536f6465abc3f180'/>
<id>463e862ac63ef27fca423782536f6465abc3f180</id>
<content type='text'>
Since commit 69031f500865 ("swiotlb: Set dev-&gt;dma_io_tlb_mem to the
swiotlb pool used"), 'struct device' may hold a copy of the global
'io_default_tlb_mem' pointer if the device is using swiotlb for DMA. A
subsequent call to swiotlb_exit() will therefore leave dangling pointers
behind in these device structures, resulting in KASAN splats such as:

  |  BUG: KASAN: use-after-free in __iommu_dma_unmap_swiotlb+0x64/0xb0
  |  Read of size 8 at addr ffff8881d7830000 by task swapper/0/0
  |
  |  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.12.0-rc3-debug #1
  |  Hardware name: HP HP Desktop M01-F1xxx/87D6, BIOS F.12 12/17/2020
  |  Call Trace:
  |   &lt;IRQ&gt;
  |   dump_stack+0x9c/0xcf
  |   print_address_description.constprop.0+0x18/0x130
  |   kasan_report.cold+0x7f/0x111
  |   __iommu_dma_unmap_swiotlb+0x64/0xb0
  |   nvme_pci_complete_rq+0x73/0x130
  |   blk_complete_reqs+0x6f/0x80
  |   __do_softirq+0xfc/0x3be

Convert 'io_default_tlb_mem' to a static structure, so that the
per-device pointers remain valid after swiotlb_exit() has been invoked.
All users are updated to reference the static structure directly, using
the 'nslabs' field to determine whether swiotlb has been initialised.
The 'slots' array is still allocated dynamically and referenced via a
pointer rather than a flexible array member.

Cc: Claire Chang &lt;tientzu@chromium.org&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Robin Murphy &lt;robin.murphy@arm.com&gt;
Cc: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Fixes: 69031f500865 ("swiotlb: Set dev-&gt;dma_io_tlb_mem to the swiotlb pool used")
Reported-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Tested-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Tested-by: Claire Chang &lt;tientzu@chromium.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Konrad Rzeszutek Wilk &lt;konrad@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since commit 69031f500865 ("swiotlb: Set dev-&gt;dma_io_tlb_mem to the
swiotlb pool used"), 'struct device' may hold a copy of the global
'io_default_tlb_mem' pointer if the device is using swiotlb for DMA. A
subsequent call to swiotlb_exit() will therefore leave dangling pointers
behind in these device structures, resulting in KASAN splats such as:

  |  BUG: KASAN: use-after-free in __iommu_dma_unmap_swiotlb+0x64/0xb0
  |  Read of size 8 at addr ffff8881d7830000 by task swapper/0/0
  |
  |  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.12.0-rc3-debug #1
  |  Hardware name: HP HP Desktop M01-F1xxx/87D6, BIOS F.12 12/17/2020
  |  Call Trace:
  |   &lt;IRQ&gt;
  |   dump_stack+0x9c/0xcf
  |   print_address_description.constprop.0+0x18/0x130
  |   kasan_report.cold+0x7f/0x111
  |   __iommu_dma_unmap_swiotlb+0x64/0xb0
  |   nvme_pci_complete_rq+0x73/0x130
  |   blk_complete_reqs+0x6f/0x80
  |   __do_softirq+0xfc/0x3be

Convert 'io_default_tlb_mem' to a static structure, so that the
per-device pointers remain valid after swiotlb_exit() has been invoked.
All users are updated to reference the static structure directly, using
the 'nslabs' field to determine whether swiotlb has been initialised.
The 'slots' array is still allocated dynamically and referenced via a
pointer rather than a flexible array member.

Cc: Claire Chang &lt;tientzu@chromium.org&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Robin Murphy &lt;robin.murphy@arm.com&gt;
Cc: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Fixes: 69031f500865 ("swiotlb: Set dev-&gt;dma_io_tlb_mem to the swiotlb pool used")
Reported-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Tested-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Tested-by: Claire Chang &lt;tientzu@chromium.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Konrad Rzeszutek Wilk &lt;konrad@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>driver core: Prevent warning when removing a device link from unregistered consumer</title>
<updated>2021-07-21T15:28:42+00:00</updated>
<author>
<name>Adrian Hunter</name>
<email>adrian.hunter@intel.com</email>
</author>
<published>2021-07-16T11:44:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e64daad660a0c9ace3acdc57099fffe5ed83f977'/>
<id>e64daad660a0c9ace3acdc57099fffe5ed83f977</id>
<content type='text'>
sysfs_remove_link() causes a warning if the parent directory does not
exist. That can happen if the device link consumer has not been registered.
So do not attempt sysfs_remove_link() in that case.

Fixes: 287905e68dd29 ("driver core: Expose device link details in sysfs")
Signed-off-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: stable@vger.kernel.org # 5.9+
Reviewed-by: Rafael J. Wysocki &lt;rafael@kernel.org&gt;
Link: https://lore.kernel.org/r/20210716114408.17320-2-adrian.hunter@intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
sysfs_remove_link() causes a warning if the parent directory does not
exist. That can happen if the device link consumer has not been registered.
So do not attempt sysfs_remove_link() in that case.

Fixes: 287905e68dd29 ("driver core: Expose device link details in sysfs")
Signed-off-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: stable@vger.kernel.org # 5.9+
Reviewed-by: Rafael J. Wysocki &lt;rafael@kernel.org&gt;
Link: https://lore.kernel.org/r/20210716114408.17320-2-adrian.hunter@intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>printk: index: Add indexing support to dev_printk</title>
<updated>2021-07-19T10:13:06+00:00</updated>
<author>
<name>Chris Down</name>
<email>chris@chrisdown.name</email>
</author>
<published>2021-06-15T16:52:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ad7d61f159db73974f1b0352f21afe04b0bbd920'/>
<id>ad7d61f159db73974f1b0352f21afe04b0bbd920</id>
<content type='text'>
While for most kinds of issues we have counters, tracepoints, or metrics
with a stable interface which can reliably be used to indicate issues,
in order to react to production issues quickly we sometimes need to work
with the interface which most kernel developers naturally use when
developing: printk, and printk-esques like dev_printk.

dev_printk is by far the most likely custom subsystem printk to benefit
from the printk indexing infrastructure, since niche device issues
brought about by production changes, firmware upgrades, and the like are
one of the most common things that we need printk infrastructure's
assistance to monitor.

Often these errors were never expected to practically manifest in
reality, and exhibit in code without extensive (or any) metrics present.
As such, there are typically very few options for issue detection
available to those with large fleets at the time the incident happens,
and we thus benefit strongly from monitoring netconsole in these
instances.

As such, add the infrastructure for dev_printk to be indexed in the
printk index. Even on a minimal kernel config, the coverage of the base
kernel's printk index is significantly improved:

Before:

    [root@ktst ~]# wc -l /sys/kernel/debug/printk/index/vmlinux
    4497 /sys/kernel/debug/printk/index/vmlinux

After:

    [root@ktst ~]# wc -l /sys/kernel/debug/printk/index/vmlinux
    5573 /sys/kernel/debug/printk/index/vmlinux

In terms of implementation, in order to trivially disambiguate them,
dev_printk is now a macro which wraps _dev_printk.

Signed-off-by: Chris Down &lt;chris@chrisdown.name&gt;
Cc: Petr Mladek &lt;pmladek@suse.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Rasmus Villemoes &lt;linux@rasmusvillemoes.dk&gt;
Reviewed-by: Petr Mladek &lt;pmladek@suse.com&gt;
Tested-by: Petr Mladek &lt;pmladek@suse.com&gt;
Acked-by: Andy Shevchenko &lt;andy.shevchenko@gmail.com&gt;
Signed-off-by: Petr Mladek &lt;pmladek@suse.com&gt;
Link: https://lore.kernel.org/r/959c7aed1017cb2c9de922e0a820d397e29c6a5a.1623775748.git.chris@chrisdown.name
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
While for most kinds of issues we have counters, tracepoints, or metrics
with a stable interface which can reliably be used to indicate issues,
in order to react to production issues quickly we sometimes need to work
with the interface which most kernel developers naturally use when
developing: printk, and printk-esques like dev_printk.

dev_printk is by far the most likely custom subsystem printk to benefit
from the printk indexing infrastructure, since niche device issues
brought about by production changes, firmware upgrades, and the like are
one of the most common things that we need printk infrastructure's
assistance to monitor.

Often these errors were never expected to practically manifest in
reality, and exhibit in code without extensive (or any) metrics present.
As such, there are typically very few options for issue detection
available to those with large fleets at the time the incident happens,
and we thus benefit strongly from monitoring netconsole in these
instances.

As such, add the infrastructure for dev_printk to be indexed in the
printk index. Even on a minimal kernel config, the coverage of the base
kernel's printk index is significantly improved:

Before:

    [root@ktst ~]# wc -l /sys/kernel/debug/printk/index/vmlinux
    4497 /sys/kernel/debug/printk/index/vmlinux

After:

    [root@ktst ~]# wc -l /sys/kernel/debug/printk/index/vmlinux
    5573 /sys/kernel/debug/printk/index/vmlinux

In terms of implementation, in order to trivially disambiguate them,
dev_printk is now a macro which wraps _dev_printk.

Signed-off-by: Chris Down &lt;chris@chrisdown.name&gt;
Cc: Petr Mladek &lt;pmladek@suse.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Rasmus Villemoes &lt;linux@rasmusvillemoes.dk&gt;
Reviewed-by: Petr Mladek &lt;pmladek@suse.com&gt;
Tested-by: Petr Mladek &lt;pmladek@suse.com&gt;
Acked-by: Andy Shevchenko &lt;andy.shevchenko@gmail.com&gt;
Signed-off-by: Petr Mladek &lt;pmladek@suse.com&gt;
Link: https://lore.kernel.org/r/959c7aed1017cb2c9de922e0a820d397e29c6a5a.1623775748.git.chris@chrisdown.name
</pre>
</div>
</content>
</entry>
<entry>
<title>driver core: Split device_platform_notify()</title>
<updated>2021-07-16T17:17:05+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-07-12T17:28:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b2ebd9dd52670a931e8f1bd77d70c57f9aa186a5'/>
<id>b2ebd9dd52670a931e8f1bd77d70c57f9aa186a5</id>
<content type='text'>
Split device_platform_notify_remove) out of device_platform_notify()
and call the latter on device addition and the former on device
removal.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Split device_platform_notify_remove) out of device_platform_notify()
and call the latter on device addition and the former on device
removal.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
