<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/kernel, branch v6.9</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>timers/migration: Prevent out of bounds access on failure</title>
<updated>2024-05-08T09:19:43+00:00</updated>
<author>
<name>Levi Yun</name>
<email>ppbuk5246@gmail.com</email>
</author>
<published>2024-05-06T04:10:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d7ad05c86e2191bd66e5b62fca8da53c4a53484f'/>
<id>d7ad05c86e2191bd66e5b62fca8da53c4a53484f</id>
<content type='text'>
When tmigr_setup_groups() fails the level 0 group allocation, then the
cleanup derefences index -1 of the local stack array.

Prevent this by checking the loop condition first.

Fixes: 7ee988770326 ("timers: Implement the hierarchical pull model")
Signed-off-by: Levi Yun &lt;ppbuk5246@gmail.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Anna-Maria Behnsen &lt;anna-maria@linutronix.de&gt;
Link: https://lore.kernel.org/r/20240506041059.86877-1-ppbuk5246@gmail.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When tmigr_setup_groups() fails the level 0 group allocation, then the
cleanup derefences index -1 of the local stack array.

Prevent this by checking the loop condition first.

Fixes: 7ee988770326 ("timers: Implement the hierarchical pull model")
Signed-off-by: Levi Yun &lt;ppbuk5246@gmail.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Anna-Maria Behnsen &lt;anna-maria@linutronix.de&gt;
Link: https://lore.kernel.org/r/20240506041059.86877-1-ppbuk5246@gmail.com
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'irq-urgent-2024-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2024-05-05T17:12:32+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-05-05T17:12:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=80f8b450bfc12b1087ca67c84071d3524bedc080'/>
<id>80f8b450bfc12b1087ca67c84071d3524bedc080</id>
<content type='text'>
Pull irq fix from Ingo Molnar:
 "Fix suspicious RCU usage in __do_softirq()"

* tag 'irq-urgent-2024-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  softirq: Fix suspicious RCU usage in __do_softirq()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull irq fix from Ingo Molnar:
 "Fix suspicious RCU usage in __do_softirq()"

* tag 'irq-urgent-2024-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  softirq: Fix suspicious RCU usage in __do_softirq()
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'probes-fixes-v6.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace</title>
<updated>2024-05-05T16:56:50+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-05-05T16:56:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2c17a1cd90a5d385a7138c030e815e3effc45677'/>
<id>2c17a1cd90a5d385a7138c030e815e3effc45677</id>
<content type='text'>
Pull probes fix from Masami Hiramatsu:

 - probe-events: Fix memory leak in parsing probe argument.

   There is a memory leak (forget to free an allocated buffer) in a
   memory allocation failure path. Fix it to jump to the correct error
   handling code.

* tag 'probes-fixes-v6.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/probes: Fix memory leak in traceprobe_parse_probe_arg_body()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull probes fix from Masami Hiramatsu:

 - probe-events: Fix memory leak in parsing probe argument.

   There is a memory leak (forget to free an allocated buffer) in a
   memory allocation failure path. Fix it to jump to the correct error
   handling code.

* tag 'probes-fixes-v6.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/probes: Fix memory leak in traceprobe_parse_probe_arg_body()
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'trace-v6.9-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace</title>
<updated>2024-05-05T16:53:09+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-05-05T16:53:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e92b99ae8216dec2566711dae0a9b7b47591e315'/>
<id>e92b99ae8216dec2566711dae0a9b7b47591e315</id>
<content type='text'>
Pull tracing and tracefs fixes from Steven Rostedt:

 - Fix RCU callback of freeing an eventfs_inode.

   The freeing of the eventfs_inode from the kref going to zero freed
   the contents of the eventfs_inode and then used kfree_rcu() to free
   the inode itself. But the contents should also be protected by RCU.
   Switch to a call_rcu() that calls a function to free all of the
   eventfs_inode after the RCU synchronization.

 - The tracing subsystem maps its own descriptor to a file represented
   by eventfs. The freeing of this descriptor needs to know when the
   last reference of an eventfs_inode is released, but currently there
   is no interface for that.

   Add a "release" callback to the eventfs_inode entry array that allows
   for freeing of data that can be referenced by the eventfs_inode being
   opened. Then increment the ref counter for this descriptor when the
   eventfs_inode file is created, and decrement/free it when the last
   reference to the eventfs_inode is released and the file is removed.
   This prevents races between freeing the descriptor and the opening of
   the eventfs file.

 - Fix the permission processing of eventfs.

   The change to make the permissions of eventfs default to the mount
   point but keep track of when changes were made had a side effect that
   could cause security concerns. When the tracefs is remounted with a
   given gid or uid, all the files within it should inherit that gid or
   uid. But if the admin had changed the permission of some file within
   the tracefs file system, it would not get updated by the remount.

   This caused the kselftest of file permissions to fail the second time
   it is run. The first time, all changes would look fine, but the
   second time, because the changes were "saved", the remount did not
   reset them.

   Create a link list of all existing tracefs inodes, and clear the
   saved flags on them on a remount if the remount changes the
   corresponding gid or uid fields.

   This also simplifies the code by removing the distinction between the
   toplevel eventfs and an instance eventfs. They should both act the
   same. They were different because of a misconception due to the
   remount not resetting the flags. Now that remount resets all the
   files and directories to default to the root node if a uid/gid is
   specified, it makes the logic simpler to implement.

* tag 'trace-v6.9-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  eventfs: Have "events" directory get permissions from its parent
  eventfs: Do not treat events directory different than other directories
  eventfs: Do not differentiate the toplevel events directory
  tracefs: Still use mount point as default permissions for instances
  tracefs: Reset permissions on remount if permissions are options
  eventfs: Free all of the eventfs_inode after RCU
  eventfs/tracing: Add callback for release of an eventfs_inode
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull tracing and tracefs fixes from Steven Rostedt:

 - Fix RCU callback of freeing an eventfs_inode.

   The freeing of the eventfs_inode from the kref going to zero freed
   the contents of the eventfs_inode and then used kfree_rcu() to free
   the inode itself. But the contents should also be protected by RCU.
   Switch to a call_rcu() that calls a function to free all of the
   eventfs_inode after the RCU synchronization.

 - The tracing subsystem maps its own descriptor to a file represented
   by eventfs. The freeing of this descriptor needs to know when the
   last reference of an eventfs_inode is released, but currently there
   is no interface for that.

   Add a "release" callback to the eventfs_inode entry array that allows
   for freeing of data that can be referenced by the eventfs_inode being
   opened. Then increment the ref counter for this descriptor when the
   eventfs_inode file is created, and decrement/free it when the last
   reference to the eventfs_inode is released and the file is removed.
   This prevents races between freeing the descriptor and the opening of
   the eventfs file.

 - Fix the permission processing of eventfs.

   The change to make the permissions of eventfs default to the mount
   point but keep track of when changes were made had a side effect that
   could cause security concerns. When the tracefs is remounted with a
   given gid or uid, all the files within it should inherit that gid or
   uid. But if the admin had changed the permission of some file within
   the tracefs file system, it would not get updated by the remount.

   This caused the kselftest of file permissions to fail the second time
   it is run. The first time, all changes would look fine, but the
   second time, because the changes were "saved", the remount did not
   reset them.

   Create a link list of all existing tracefs inodes, and clear the
   saved flags on them on a remount if the remount changes the
   corresponding gid or uid fields.

   This also simplifies the code by removing the distinction between the
   toplevel eventfs and an instance eventfs. They should both act the
   same. They were different because of a misconception due to the
   remount not resetting the flags. Now that remount resets all the
   files and directories to default to the root node if a uid/gid is
   specified, it makes the logic simpler to implement.

* tag 'trace-v6.9-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  eventfs: Have "events" directory get permissions from its parent
  eventfs: Do not treat events directory different than other directories
  eventfs: Do not differentiate the toplevel events directory
  tracefs: Still use mount point as default permissions for instances
  tracefs: Reset permissions on remount if permissions are options
  eventfs: Free all of the eventfs_inode after RCU
  eventfs/tracing: Add callback for release of an eventfs_inode
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'dma-mapping-6.9-2024-05-04' of git://git.infradead.org/users/hch/dma-mapping</title>
<updated>2024-05-05T16:49:21+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-05-05T16:49:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4fbcf58590a85cdabc48c1541d4f7031b22829f0'/>
<id>4fbcf58590a85cdabc48c1541d4f7031b22829f0</id>
<content type='text'>
Pull dma-mapping fix from Christoph Hellwig:

 - fix the combination of restricted pools and dynamic swiotlb
   (Will Deacon)

* tag 'dma-mapping-6.9-2024-05-04' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull dma-mapping fix from Christoph Hellwig:

 - fix the combination of restricted pools and dynamic swiotlb
   (Will Deacon)

* tag 'dma-mapping-6.9-2024-05-04' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y
</pre>
</div>
</content>
</entry>
<entry>
<title>eventfs/tracing: Add callback for release of an eventfs_inode</title>
<updated>2024-05-04T08:25:37+00:00</updated>
<author>
<name>Steven Rostedt (Google)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2024-05-02T13:03:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b63db58e2fa5d6963db9c45df88e60060f0ff35f'/>
<id>b63db58e2fa5d6963db9c45df88e60060f0ff35f</id>
<content type='text'>
Synthetic events create and destroy tracefs files when they are created
and removed. The tracing subsystem has its own file descriptor
representing the state of the events attached to the tracefs files.
There's a race between the eventfs files and this file descriptor of the
tracing system where the following can cause an issue:

With two scripts 'A' and 'B' doing:

  Script 'A':
    echo "hello int aaa" &gt; /sys/kernel/tracing/synthetic_events
    while :
    do
      echo 0 &gt; /sys/kernel/tracing/events/synthetic/hello/enable
    done

  Script 'B':
    echo &gt; /sys/kernel/tracing/synthetic_events

Script 'A' creates a synthetic event "hello" and then just writes zero
into its enable file.

Script 'B' removes all synthetic events (including the newly created
"hello" event).

What happens is that the opening of the "enable" file has:

 {
	struct trace_event_file *file = inode-&gt;i_private;
	int ret;

	ret = tracing_check_open_get_tr(file-&gt;tr);
 [..]

But deleting the events frees the "file" descriptor, and a "use after
free" happens with the dereference at "file-&gt;tr".

The file descriptor does have a reference counter, but there needs to be a
way to decrement it from the eventfs when the eventfs_inode is removed
that represents this file descriptor.

Add an optional "release" callback to the eventfs_entry array structure,
that gets called when the eventfs file is about to be removed. This allows
for the creating on the eventfs file to increment the tracing file
descriptor ref counter. When the eventfs file is deleted, it can call the
release function that will call the put function for the tracing file
descriptor.

This will protect the tracing file from being freed while a eventfs file
that references it is being opened.

Link: https://lore.kernel.org/linux-trace-kernel/20240426073410.17154-1-Tze-nan.Wu@mediatek.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240502090315.448cba46@gandalf.local.home

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Fixes: 5790b1fb3d672 ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: Tze-nan wu &lt;Tze-nan.Wu@mediatek.com&gt;
Tested-by: Tze-nan Wu (吳澤南) &lt;Tze-nan.Wu@mediatek.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Synthetic events create and destroy tracefs files when they are created
and removed. The tracing subsystem has its own file descriptor
representing the state of the events attached to the tracefs files.
There's a race between the eventfs files and this file descriptor of the
tracing system where the following can cause an issue:

With two scripts 'A' and 'B' doing:

  Script 'A':
    echo "hello int aaa" &gt; /sys/kernel/tracing/synthetic_events
    while :
    do
      echo 0 &gt; /sys/kernel/tracing/events/synthetic/hello/enable
    done

  Script 'B':
    echo &gt; /sys/kernel/tracing/synthetic_events

Script 'A' creates a synthetic event "hello" and then just writes zero
into its enable file.

Script 'B' removes all synthetic events (including the newly created
"hello" event).

What happens is that the opening of the "enable" file has:

 {
	struct trace_event_file *file = inode-&gt;i_private;
	int ret;

	ret = tracing_check_open_get_tr(file-&gt;tr);
 [..]

But deleting the events frees the "file" descriptor, and a "use after
free" happens with the dereference at "file-&gt;tr".

The file descriptor does have a reference counter, but there needs to be a
way to decrement it from the eventfs when the eventfs_inode is removed
that represents this file descriptor.

Add an optional "release" callback to the eventfs_entry array structure,
that gets called when the eventfs file is about to be removed. This allows
for the creating on the eventfs file to increment the tracing file
descriptor ref counter. When the eventfs file is deleted, it can call the
release function that will call the put function for the tracing file
descriptor.

This will protect the tracing file from being freed while a eventfs file
that references it is being opened.

Link: https://lore.kernel.org/linux-trace-kernel/20240426073410.17154-1-Tze-nan.Wu@mediatek.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240502090315.448cba46@gandalf.local.home

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Fixes: 5790b1fb3d672 ("eventfs: Remove eventfs_file and just use eventfs_inode")
Reported-by: Tze-nan wu &lt;Tze-nan.Wu@mediatek.com&gt;
Tested-by: Tze-nan Wu (吳澤南) &lt;Tze-nan.Wu@mediatek.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'net-6.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2024-05-02T15:51:47+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-05-02T15:51:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=545c494465d24b10a4370545ba213c0916f70b95'/>
<id>545c494465d24b10a4370545ba213c0916f70b95</id>
<content type='text'>
Pull networking fixes from Paolo Abeni:
 "Including fixes from bpf.

  Relatively calm week, likely due to public holiday in most places. No
  known outstanding regressions.

  Current release - regressions:

   - rxrpc: fix wrong alignmask in __page_frag_alloc_align()

   - eth: e1000e: change usleep_range to udelay in PHY mdic access

  Previous releases - regressions:

   - gro: fix udp bad offset in socket lookup

   - bpf: fix incorrect runtime stat for arm64

   - tipc: fix UAF in error path

   - netfs: fix a potential infinite loop in extract_user_to_sg()

   - eth: ice: ensure the copied buf is NUL terminated

   - eth: qeth: fix kernel panic after setting hsuid

  Previous releases - always broken:

   - bpf:
       - verifier: prevent userspace memory access
       - xdp: use flags field to disambiguate broadcast redirect

   - bridge: fix multicast-to-unicast with fraglist GSO

   - mptcp: ensure snd_nxt is properly initialized on connect

   - nsh: fix outer header access in nsh_gso_segment().

   - eth: bcmgenet: fix racing registers access

   - eth: vxlan: fix stats counters.

  Misc:

   - a bunch of MAINTAINERS file updates"

* tag 'net-6.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (45 commits)
  MAINTAINERS: mark MYRICOM MYRI-10G as Orphan
  MAINTAINERS: remove Ariel Elior
  net: gro: add flush check in udp_gro_receive_segment
  net: gro: fix udp bad offset in socket lookup by adding {inner_}network_offset to napi_gro_cb
  ipv4: Fix uninit-value access in __ip_make_skb()
  s390/qeth: Fix kernel panic after setting hsuid
  vxlan: Pull inner IP header in vxlan_rcv().
  tipc: fix a possible memleak in tipc_buf_append
  tipc: fix UAF in error path
  rxrpc: Clients must accept conn from any address
  net: core: reject skb_copy(_expand) for fraglist GSO skbs
  net: bridge: fix multicast-to-unicast with fraglist GSO
  mptcp: ensure snd_nxt is properly initialized on connect
  e1000e: change usleep_range to udelay in PHY mdic access
  net: dsa: mv88e6xxx: Fix number of databases for 88E6141 / 88E6341
  cxgb4: Properly lock TX queue for the selftest.
  rxrpc: Fix using alignmask being zero for __page_frag_alloc_align()
  vxlan: Add missing VNI filter counter update in arp_reduce().
  vxlan: Fix racy device stats updates.
  net: qede: use return from qede_parse_actions()
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull networking fixes from Paolo Abeni:
 "Including fixes from bpf.

  Relatively calm week, likely due to public holiday in most places. No
  known outstanding regressions.

  Current release - regressions:

   - rxrpc: fix wrong alignmask in __page_frag_alloc_align()

   - eth: e1000e: change usleep_range to udelay in PHY mdic access

  Previous releases - regressions:

   - gro: fix udp bad offset in socket lookup

   - bpf: fix incorrect runtime stat for arm64

   - tipc: fix UAF in error path

   - netfs: fix a potential infinite loop in extract_user_to_sg()

   - eth: ice: ensure the copied buf is NUL terminated

   - eth: qeth: fix kernel panic after setting hsuid

  Previous releases - always broken:

   - bpf:
       - verifier: prevent userspace memory access
       - xdp: use flags field to disambiguate broadcast redirect

   - bridge: fix multicast-to-unicast with fraglist GSO

   - mptcp: ensure snd_nxt is properly initialized on connect

   - nsh: fix outer header access in nsh_gso_segment().

   - eth: bcmgenet: fix racing registers access

   - eth: vxlan: fix stats counters.

  Misc:

   - a bunch of MAINTAINERS file updates"

* tag 'net-6.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (45 commits)
  MAINTAINERS: mark MYRICOM MYRI-10G as Orphan
  MAINTAINERS: remove Ariel Elior
  net: gro: add flush check in udp_gro_receive_segment
  net: gro: fix udp bad offset in socket lookup by adding {inner_}network_offset to napi_gro_cb
  ipv4: Fix uninit-value access in __ip_make_skb()
  s390/qeth: Fix kernel panic after setting hsuid
  vxlan: Pull inner IP header in vxlan_rcv().
  tipc: fix a possible memleak in tipc_buf_append
  tipc: fix UAF in error path
  rxrpc: Clients must accept conn from any address
  net: core: reject skb_copy(_expand) for fraglist GSO skbs
  net: bridge: fix multicast-to-unicast with fraglist GSO
  mptcp: ensure snd_nxt is properly initialized on connect
  e1000e: change usleep_range to udelay in PHY mdic access
  net: dsa: mv88e6xxx: Fix number of databases for 88E6141 / 88E6341
  cxgb4: Properly lock TX queue for the selftest.
  rxrpc: Fix using alignmask being zero for __page_frag_alloc_align()
  vxlan: Add missing VNI filter counter update in arp_reduce().
  vxlan: Fix racy device stats updates.
  net: qede: use return from qede_parse_actions()
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y</title>
<updated>2024-05-02T12:57:04+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will@kernel.org</email>
</author>
<published>2024-05-02T09:37:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=75961ffb5cb3e5196f19cae7683f35cc88b50800'/>
<id>75961ffb5cb3e5196f19cae7683f35cc88b50800</id>
<content type='text'>
Using restricted DMA pools (CONFIG_DMA_RESTRICTED_POOL=y) in conjunction
with dynamic SWIOTLB (CONFIG_SWIOTLB_DYNAMIC=y) leads to the following
crash when initialising the restricted pools at boot-time:

  | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008
  | Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
  | pc : rmem_swiotlb_device_init+0xfc/0x1ec
  | lr : rmem_swiotlb_device_init+0xf0/0x1ec
  | Call trace:
  |  rmem_swiotlb_device_init+0xfc/0x1ec
  |  of_reserved_mem_device_init_by_idx+0x18c/0x238
  |  of_dma_configure_id+0x31c/0x33c
  |  platform_dma_configure+0x34/0x80

faddr2line reveals that the crash is in the list validation code:

  include/linux/list.h:83
  include/linux/rculist.h:79
  include/linux/rculist.h:106
  kernel/dma/swiotlb.c:306
  kernel/dma/swiotlb.c:1695

because add_mem_pool() is trying to list_add_rcu() to a NULL
'mem-&gt;pools'.

Fix the crash by initialising the 'mem-&gt;pools' list_head in
rmem_swiotlb_device_init() before calling add_mem_pool().

Reported-by: Nikita Ioffe &lt;ioffe@google.com&gt;
Tested-by: Nikita Ioffe &lt;ioffe@google.com&gt;
Fixes: 1aaa736815eb ("swiotlb: allocate a new memory pool when existing pools are full")
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Using restricted DMA pools (CONFIG_DMA_RESTRICTED_POOL=y) in conjunction
with dynamic SWIOTLB (CONFIG_SWIOTLB_DYNAMIC=y) leads to the following
crash when initialising the restricted pools at boot-time:

  | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008
  | Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
  | pc : rmem_swiotlb_device_init+0xfc/0x1ec
  | lr : rmem_swiotlb_device_init+0xf0/0x1ec
  | Call trace:
  |  rmem_swiotlb_device_init+0xfc/0x1ec
  |  of_reserved_mem_device_init_by_idx+0x18c/0x238
  |  of_dma_configure_id+0x31c/0x33c
  |  platform_dma_configure+0x34/0x80

faddr2line reveals that the crash is in the list validation code:

  include/linux/list.h:83
  include/linux/rculist.h:79
  include/linux/rculist.h:106
  kernel/dma/swiotlb.c:306
  kernel/dma/swiotlb.c:1695

because add_mem_pool() is trying to list_add_rcu() to a NULL
'mem-&gt;pools'.

Fix the crash by initialising the 'mem-&gt;pools' list_head in
rmem_swiotlb_device_init() before calling add_mem_pool().

Reported-by: Nikita Ioffe &lt;ioffe@google.com&gt;
Tested-by: Nikita Ioffe &lt;ioffe@google.com&gt;
Fixes: 1aaa736815eb ("swiotlb: allocate a new memory pool when existing pools are full")
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'wq-for-6.9-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq</title>
<updated>2024-04-29T22:57:37+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-04-29T22:57:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=98369dccd2f8e16bf4c6621053af7aa4821dcf8e'/>
<id>98369dccd2f8e16bf4c6621053af7aa4821dcf8e</id>
<content type='text'>
Pull workqueue fixes from Tejun Heo:
 "Two doc update patches and the following three fixes:

   - On single node systems, the default pool is used but the
     node_nr_active for the default pool was set to min_active. This
     effectively limited the max concurrency of unbound pools on single
     node systems to 8 causing performance regressions on some
     workloads. Fixed by setting the default pool's node_nr_active to
     max_active.

   - wq_update_node_max_active() could trigger divide-by-zero if the
     intersection between the allowed CPUs for an unbound workqueue and
     online CPUs becomes empty.

   - When kick_pool() was trying to repatriate a worker to a CPU in its
     pod by setting task-&gt;wake_cpu, it didn't consider whether the CPU
     being selected is online or not which obviously can lead to
     subobtimal behaviors. On s390, this triggered a crash in arch code.
     The workqueue patch removes the gross misbehavior but doesn't fix
     the crash completely as there's a race window in which CPUs can go
     down after wake_cpu is set. Need to decide whether the fix should
     be on the core or arch side"

* tag 'wq-for-6.9-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Fix divide error in wq_update_node_max_active()
  workqueue: The default node_nr_active should have its max set to max_active
  workqueue: Fix selection of wake_cpu in kick_pool()
  docs/zh_CN: core-api: Update translation of workqueue.rst to 6.9-rc1
  Documentation/core-api: Update events_freezable_power references.
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull workqueue fixes from Tejun Heo:
 "Two doc update patches and the following three fixes:

   - On single node systems, the default pool is used but the
     node_nr_active for the default pool was set to min_active. This
     effectively limited the max concurrency of unbound pools on single
     node systems to 8 causing performance regressions on some
     workloads. Fixed by setting the default pool's node_nr_active to
     max_active.

   - wq_update_node_max_active() could trigger divide-by-zero if the
     intersection between the allowed CPUs for an unbound workqueue and
     online CPUs becomes empty.

   - When kick_pool() was trying to repatriate a worker to a CPU in its
     pod by setting task-&gt;wake_cpu, it didn't consider whether the CPU
     being selected is online or not which obviously can lead to
     subobtimal behaviors. On s390, this triggered a crash in arch code.
     The workqueue patch removes the gross misbehavior but doesn't fix
     the crash completely as there's a race window in which CPUs can go
     down after wake_cpu is set. Need to decide whether the fix should
     be on the core or arch side"

* tag 'wq-for-6.9-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Fix divide error in wq_update_node_max_active()
  workqueue: The default node_nr_active should have its max set to max_active
  workqueue: Fix selection of wake_cpu in kick_pool()
  docs/zh_CN: core-api: Update translation of workqueue.rst to 6.9-rc1
  Documentation/core-api: Update events_freezable_power references.
</pre>
</div>
</content>
</entry>
<entry>
<title>bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS</title>
<updated>2024-04-29T15:29:29+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2024-04-29T14:47:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5af385f5f4cddf908f663974847a4083b2ff2c79'/>
<id>5af385f5f4cddf908f663974847a4083b2ff2c79</id>
<content type='text'>
bits_per() rounds up to the next power of two when passed a power of
two.  This causes crashes on some machines and configurations.

Reported-by: Михаил Новоселов &lt;m.novosyolov@rosalinux.ru&gt;
Tested-by: Ильфат Гаптрахманов &lt;i.gaptrakhmanov@rosalinux.ru&gt;
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3347
Link: https://lore.kernel.org/all/1c978cf1-2934-4e66-e4b3-e81b04cb3571@rosalinux.ru/
Fixes: f2d5dcb48f7b (bounds: support non-power-of-two CONFIG_NR_CPUS)
Cc:  &lt;stable@vger.kernel.org&gt;
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Rik van Riel &lt;riel@surriel.com&gt;
Cc: Mel Gorman &lt;mgorman@techsingularity.net&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
bits_per() rounds up to the next power of two when passed a power of
two.  This causes crashes on some machines and configurations.

Reported-by: Михаил Новоселов &lt;m.novosyolov@rosalinux.ru&gt;
Tested-by: Ильфат Гаптрахманов &lt;i.gaptrakhmanov@rosalinux.ru&gt;
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3347
Link: https://lore.kernel.org/all/1c978cf1-2934-4e66-e4b3-e81b04cb3571@rosalinux.ru/
Fixes: f2d5dcb48f7b (bounds: support non-power-of-two CONFIG_NR_CPUS)
Cc:  &lt;stable@vger.kernel.org&gt;
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Rik van Riel &lt;riel@surriel.com&gt;
Cc: Mel Gorman &lt;mgorman@techsingularity.net&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
