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<title>pm24.git/kernel, branch rust-6.8</title>
<subtitle>Unnamed repository; edit this file 'description' to name the repository.
</subtitle>
<id>https://git.kobert.dev/pm24.git/atom?h=rust-6.8</id>
<link rel='self' href='https://git.kobert.dev/pm24.git/atom?h=rust-6.8'/>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/'/>
<updated>2023-12-10T19:09:16Z</updated>
<entry>
<title>Merge tag 'sched_urgent_for_v6.7_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2023-12-10T19:09:16Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-12-10T19:09:16Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=3a87498869d6d1e7347cd01f337a77984604eb5e'/>
<id>urn:sha1:3a87498869d6d1e7347cd01f337a77984604eb5e</id>
<content type='text'>
Pull scheduler fix from Borislav Petkov:

 - Make sure tasks are thawed exactly and only once to avoid their state
   getting corrupted

* tag 'sched_urgent_for_v6.7_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  freezer,sched: Do not restore saved_state of a thawed task
</content>
</entry>
<entry>
<title>Merge tag 'perf_urgent_for_v6.7_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2023-12-10T19:03:15Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-12-10T19:03:15Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=537ccb5d28d6f398215e7f578e46ee7836f5ac47'/>
<id>urn:sha1:537ccb5d28d6f398215e7f578e46ee7836f5ac47</id>
<content type='text'>
Pull perf event fix from Borislav Petkov:

 - Make sure perf event size validation is done on every event in the
   group

* tag 'perf_urgent_for_v6.7_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix perf_event_validate_size()
</content>
</entry>
<entry>
<title>Merge tag 'trace-v6.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace</title>
<updated>2023-12-08T16:44:43Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-12-08T16:44:43Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=17894c2a7aa60a6da7495cc8500a53523e64c4b1'/>
<id>urn:sha1:17894c2a7aa60a6da7495cc8500a53523e64c4b1</id>
<content type='text'>
Pull tracing fixes from Steven Rostedt:

 - Snapshot buffer issues:

   1. When instances started allowing latency tracers, it uses a
      snapshot buffer (another buffer that is not written to but swapped
      with the main buffer that is). The snapshot buffer needs to be the
      same size as the main buffer. But when the snapshot buffers were
      added to instances, the code to make the snapshot equal to the
      main buffer still was only doing it for the main buffer and not
      the instances.

   2. Need to stop the current tracer when resizing the buffers.
      Otherwise there can be a race if the tracer decides to make a
      snapshot between resizing the main buffer and the snapshot buffer.

   3. When a tracer is "stopped" in disables both the main buffer and
      the snapshot buffer. This needs to be done for instances and not
      only the main buffer, now that instances also have a snapshot
      buffer.

 - Buffered event for filtering issues:

   When filtering is enabled, because events can be dropped often, it is
   quicker to copy the event into a temp buffer and write that into the
   main buffer if it is not filtered or just drop the event if it is,
   than to write the event into the ring buffer and then try to discard
   it. This temp buffer is allocated and needs special synchronization
   to do so. But there were some issues with that:

   1. When disabling the filter and freeing the buffer, a call to all
      CPUs is required to stop each per_cpu usage. But the code called
      smp_call_function_many() which does not include the current CPU.
      If the task is migrated to another CPU when it enables the CPUs
      via smp_call_function_many(), it will not enable the one it is
      currently on and this causes issues later on. Use
      on_each_cpu_mask() instead, which includes the current CPU.

    2.When the allocation of the buffered event fails, it can give a
      warning. But the buffered event is just an optimization (it's
      still OK to write to the ring buffer and free it). Do not WARN in
      this case.

    3.The freeing of the buffer event requires synchronization. First a
      counter is decremented to zero so that no new uses of it will
      happen. Then it sets the buffered event to NULL, and finally it
      frees the buffered event. There's a synchronize_rcu() between the
      counter decrement and the setting the variable to NULL, but only a
      smp_wmb() between that and the freeing of the buffer. It is
      theoretically possible that a user missed seeing the decrement,
      but will use the buffer after it is free. Another
      synchronize_rcu() is needed in place of that smp_wmb().

 - ring buffer timestamps on 32 bit machines

   The ring buffer timestamp on 32 bit machines has to break the 64 bit
   number into multiple values as cmpxchg is required on it, and a 64
   bit cmpxchg on 32 bit architectures is very slow. The code use to
   just use two 32 bit values and make it a 60 bit timestamp where the
   other 4 bits were used as counters for synchronization. It later came
   known that the timestamp on 32 bit still need all 64 bits in some
   cases. So 3 words were created to handle the 64 bits. But issues
   arised with this:

    1. The synchronization logic still only compared the counter with
       the first two, but not with the third number, so the
       synchronization could fail unknowingly.

    2. A check on discard of an event could race if an event happened
       between the discard and updating one of the counters. The counter
       needs to be updated (forcing an absolute timestamp and not to use
       a delta) before the actual discard happens.

* tag 'trace-v6.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Test last update in 32bit version of __rb_time_read()
  ring-buffer: Force absolute timestamp on discard of event
  tracing: Fix a possible race when disabling buffered events
  tracing: Fix a warning when allocating buffered events fails
  tracing: Fix incomplete locking when disabling buffered events
  tracing: Disable snapshot buffer when stopping instance tracers
  tracing: Stop current tracer when resizing buffer
  tracing: Always update snapshot buffer size
</content>
</entry>
<entry>
<title>Merge tag 'mm-hotfixes-stable-2023-12-07-18-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2023-12-08T16:36:23Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-12-08T16:36:23Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=8e819a7623f19534bce6d53678b581c167b5b079'/>
<id>urn:sha1:8e819a7623f19534bce6d53678b581c167b5b079</id>
<content type='text'>
Pull misc fixes from Andrew Morton:
 "31 hotfixes. Ten of these address pre-6.6 issues and are marked
  cc:stable. The remainder address post-6.6 issues or aren't considered
  serious enough to justify backporting"

* tag 'mm-hotfixes-stable-2023-12-07-18-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (31 commits)
  mm/madvise: add cond_resched() in madvise_cold_or_pageout_pte_range()
  nilfs2: prevent WARNING in nilfs_sufile_set_segment_usage()
  mm/hugetlb: have CONFIG_HUGETLB_PAGE select CONFIG_XARRAY_MULTI
  scripts/gdb: fix lx-device-list-bus and lx-device-list-class
  MAINTAINERS: drop Antti Palosaari
  highmem: fix a memory copy problem in memcpy_from_folio
  nilfs2: fix missing error check for sb_set_blocksize call
  kernel/Kconfig.kexec: drop select of KEXEC for CRASH_DUMP
  units: add missing header
  drivers/base/cpu: crash data showing should depends on KEXEC_CORE
  mm/damon/sysfs-schemes: add timeout for update_schemes_tried_regions
  scripts/gdb/tasks: fix lx-ps command error
  mm/Kconfig: make userfaultfd a menuconfig
  selftests/mm: prevent duplicate runs caused by TEST_GEN_PROGS
  mm/damon/core: copy nr_accesses when splitting region
  lib/group_cpus.c: avoid acquiring cpu hotplug lock in group_cpus_evenly
  checkstack: fix printed address
  mm/memory_hotplug: fix error handling in add_memory_resource()
  mm/memory_hotplug: add missing mem_hotplug_lock
  .mailmap: add a new address mapping for Chester Lin
  ...
</content>
</entry>
<entry>
<title>Merge tag 'net-6.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2023-12-08T01:04:13Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-12-08T01:04:13Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=5e3f5b81de80c98338bcb47c233aebefee5a4801'/>
<id>urn:sha1:5e3f5b81de80c98338bcb47c233aebefee5a4801</id>
<content type='text'>
Pull networking fixes from Jakub Kicinski:
 "Including fixes from bpf and netfilter.

  Current release - regressions:

   - veth: fix packet segmentation in veth_convert_skb_to_xdp_buff

  Current release - new code bugs:

   - tcp: assorted fixes to the new Auth Option support

  Older releases - regressions:

   - tcp: fix mid stream window clamp

   - tls: fix incorrect splice handling

   - ipv4: ip_gre: handle skb_pull() failure in ipgre_xmit()

   - dsa: mv88e6xxx: restore USXGMII support for 6393X

   - arcnet: restore support for multiple Sohard Arcnet cards

  Older releases - always broken:

   - tcp: do not accept ACK of bytes we never sent

   - require admin privileges to receive packet traces via netlink

   - packet: move reference count in packet_sock to atomic_long_t

   - bpf:
      - fix incorrect branch offset comparison with cpu=v4
      - fix prog_array_map_poke_run map poke update

   - netfilter:
      - three fixes for crashes on bad admin commands
      - xt_owner: fix race accessing sk-&gt;sk_socket, TOCTOU null-deref
      - nf_tables: fix 'exist' matching on bigendian arches

   - leds: netdev: fix RTNL handling to prevent potential deadlock

   - eth: tg3: prevent races in error/reset handling

   - eth: r8169: fix rtl8125b PAUSE storm when suspended

   - eth: r8152: improve reset and surprise removal handling

   - eth: hns: fix race between changing features and sending

   - eth: nfp: fix sleep in atomic for bonding offload"

* tag 'net-6.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (62 commits)
  vsock/virtio: fix "comparison of distinct pointer types lacks a cast" warning
  net/smc: fix missing byte order conversion in CLC handshake
  net: dsa: microchip: provide a list of valid protocols for xmit handler
  drop_monitor: Require 'CAP_SYS_ADMIN' when joining "events" group
  psample: Require 'CAP_NET_ADMIN' when joining "packets" group
  bpf: sockmap, updating the sg structure should also update curr
  net: tls, update curr on splice as well
  nfp: flower: fix for take a mutex lock in soft irq context and rcu lock
  net: dsa: mv88e6xxx: Restore USXGMII support for 6393X
  tcp: do not accept ACK of bytes we never sent
  selftests/bpf: Add test for early update in prog_array_map_poke_run
  bpf: Fix prog_array_map_poke_run map poke update
  netfilter: xt_owner: Fix for unsafe access of sk-&gt;sk_socket
  netfilter: nf_tables: validate family when identifying table via handle
  netfilter: nf_tables: bail out on mismatching dynset and set expressions
  netfilter: nf_tables: fix 'exist' matching on bigendian arches
  netfilter: nft_set_pipapo: skip inactive elements during set walk
  netfilter: bpf: fix bad registration on nf_defrag
  leds: trigger: netdev: fix RTNL handling to prevent potential deadlock
  octeontx2-af: Update Tx link register range
  ...
</content>
</entry>
<entry>
<title>Merge tag 'cgroup-for-6.7-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup</title>
<updated>2023-12-07T20:42:40Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-12-07T20:42:40Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=9ace34a8e446c1a566f3b0a3e0c4c483987e39a6'/>
<id>urn:sha1:9ace34a8e446c1a566f3b0a3e0c4c483987e39a6</id>
<content type='text'>
Pull cgroup fix from Tejun Heo:
 "Just one fix.

  Commit f5d39b020809 ("freezer,sched: Rewrite core freezer logic")
  changed how freezing state is recorded which made cgroup_freezing()
  disagree with the actual state of the task while thawing triggering a
  warning. Fix it by updating cgroup_freezing()"

* tag 'cgroup-for-6.7-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup_freezer: cgroup_freezing: Check if not frozen
</content>
</entry>
<entry>
<title>Merge tag 'wq-for-6.7-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq</title>
<updated>2023-12-07T20:36:32Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-12-07T20:36:32Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=e0348c1f686a939222a2cbe7f3861e356b60d9b6'/>
<id>urn:sha1:e0348c1f686a939222a2cbe7f3861e356b60d9b6</id>
<content type='text'>
Pull workqueue fix from Tejun Heo:
 "Just one patch to fix a bug which can crash the kernel if the
  housekeeping and wq_unbound_cpu cpumask configuration combination
  leaves the latter empty"

* tag 'wq-for-6.7-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Make sure that wq_unbound_cpumask is never empty
</content>
</entry>
<entry>
<title>kernel/Kconfig.kexec: drop select of KEXEC for CRASH_DUMP</title>
<updated>2023-12-07T00:12:48Z</updated>
<author>
<name>Baoquan He</name>
<email>bhe@redhat.com</email>
</author>
<published>2023-11-28T05:44:57Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=dccf78d39f1069a5ddf4328bf0c97aa5f2f4296e'/>
<id>urn:sha1:dccf78d39f1069a5ddf4328bf0c97aa5f2f4296e</id>
<content type='text'>
Ignat Korchagin complained that a potential config regression was
introduced by commit 89cde455915f ("kexec: consolidate kexec and crash
options into kernel/Kconfig.kexec").  Before the commit, CONFIG_CRASH_DUMP
has no dependency on CONFIG_KEXEC.  After the commit, CRASH_DUMP selects
KEXEC.  That enforces system to have CONFIG_KEXEC=y as long as
CONFIG_CRASH_DUMP=Y which people may not want.

In Ignat's case, he sets CONFIG_CRASH_DUMP=y, CONFIG_KEXEC_FILE=y and
CONFIG_KEXEC=n because kexec_load interface could have security issue if
kernel/initrd has no chance to be signed and verified.

CRASH_DUMP has select of KEXEC because Eric, author of above commit, met a
LKP report of build failure when posting patch of earlier version.  Please
see below link to get detail of the LKP report:

    https://lore.kernel.org/all/3e8eecd1-a277-2cfb-690e-5de2eb7b988e@oracle.com/T/#u

In fact, that LKP report is triggered because arm's &lt;asm/kexec.h&gt; is
wrapped in CONFIG_KEXEC ifdeffery scope.  That is wrong.  CONFIG_KEXEC
controls the enabling/disabling of kexec_load interface, but not kexec
feature.  Removing the wrongly added CONFIG_KEXEC ifdeffery scope in
&lt;asm/kexec.h&gt; of arm allows us to drop the select KEXEC for CRASH_DUMP. 
Meanwhile, change arch/arm/kernel/Makefile to let machine_kexec.o
relocate_kernel.o depend on KEXEC_CORE.

Link: https://lkml.kernel.org/r/20231128054457.659452-1-bhe@redhat.com
Fixes: 89cde455915f ("kexec: consolidate kexec and crash options into kernel/Kconfig.kexec")
Signed-off-by: Baoquan He &lt;bhe@redhat.com&gt;
Reported-by: Ignat Korchagin &lt;ignat@cloudflare.com&gt;
Tested-by: Ignat Korchagin &lt;ignat@cloudflare.com&gt;	[compile-time only]
Tested-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Reviewed-by: Eric DeVolder &lt;eric_devolder@yahoo.com&gt;
Tested-by: Eric DeVolder &lt;eric_devolder@yahoo.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: Fix prog_array_map_poke_run map poke update</title>
<updated>2023-12-06T21:40:16Z</updated>
<author>
<name>Jiri Olsa</name>
<email>jolsa@kernel.org</email>
</author>
<published>2023-12-06T08:30:40Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=4b7de801606e504e69689df71475d27e35336fb3'/>
<id>urn:sha1:4b7de801606e504e69689df71475d27e35336fb3</id>
<content type='text'>
Lee pointed out issue found by syscaller [0] hitting BUG in prog array
map poke update in prog_array_map_poke_run function due to error value
returned from bpf_arch_text_poke function.

There's race window where bpf_arch_text_poke can fail due to missing
bpf program kallsym symbols, which is accounted for with check for
-EINVAL in that BUG_ON call.

The problem is that in such case we won't update the tail call jump
and cause imbalance for the next tail call update check which will
fail with -EBUSY in bpf_arch_text_poke.

I'm hitting following race during the program load:

  CPU 0                             CPU 1

  bpf_prog_load
    bpf_check
      do_misc_fixups
        prog_array_map_poke_track

                                    map_update_elem
                                      bpf_fd_array_map_update_elem
                                        prog_array_map_poke_run

                                          bpf_arch_text_poke returns -EINVAL

    bpf_prog_kallsyms_add

After bpf_arch_text_poke (CPU 1) fails to update the tail call jump, the next
poke update fails on expected jump instruction check in bpf_arch_text_poke
with -EBUSY and triggers the BUG_ON in prog_array_map_poke_run.

Similar race exists on the program unload.

Fixing this by moving the update to bpf_arch_poke_desc_update function which
makes sure we call __bpf_arch_text_poke that skips the bpf address check.

Each architecture has slightly different approach wrt looking up bpf address
in bpf_arch_text_poke, so instead of splitting the function or adding new
'checkip' argument in previous version, it seems best to move the whole
map_poke_run update as arch specific code.

  [0] https://syzkaller.appspot.com/bug?extid=97a4fe20470e9bc30810

Fixes: ebf7d1f508a7 ("bpf, x64: rework pro/epilogue and tailcall handling in JIT")
Reported-by: syzbot+97a4fe20470e9bc30810@syzkaller.appspotmail.com
Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: Yonghong Song &lt;yonghong.song@linux.dev&gt;
Cc: Lee Jones &lt;lee@kernel.org&gt;
Cc: Maciej Fijalkowski &lt;maciej.fijalkowski@intel.com&gt;
Link: https://lore.kernel.org/bpf/20231206083041.1306660-2-jolsa@kernel.org
</content>
</entry>
<entry>
<title>ring-buffer: Test last update in 32bit version of __rb_time_read()</title>
<updated>2023-12-06T20:01:49Z</updated>
<author>
<name>Steven Rostedt (Google)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2023-12-06T15:00:50Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=f458a1453424e03462b5bb539673c9a3cddda480'/>
<id>urn:sha1:f458a1453424e03462b5bb539673c9a3cddda480</id>
<content type='text'>
Since 64 bit cmpxchg() is very expensive on 32bit architectures, the
timestamp used by the ring buffer does some interesting tricks to be able
to still have an atomic 64 bit number. It originally just used 60 bits and
broke it up into two 32 bit words where the extra 2 bits were used for
synchronization. But this was not enough for all use cases, and all 64
bits were required.

The 32bit version of the ring buffer timestamp was then broken up into 3
32bit words using the same counter trick. But one update was not done. The
check to see if the read operation was done without interruption only
checked the first two words and not last one (like it had before this
update). Fix it by making sure all three updates happen without
interruption by comparing the initial counter with the last updated
counter.

Link: https://lore.kernel.org/linux-trace-kernel/20231206100050.3100b7bb@gandalf.local.home

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Fixes: f03f2abce4f39 ("ring-buffer: Have 32 bit time stamps use all 64 bits")
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
</feed>
