<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git, branch v6.6.85</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.6.85</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.6.85'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2025-03-28T20:59:57+00:00</updated>
<entry>
<title>Linux 6.6.85</title>
<updated>2025-03-28T20:59:57+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2025-03-28T20:59:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d57a7c6169607dd09157ccf257e556fb75444f28'/>
<id>urn:sha1:d57a7c6169607dd09157ccf257e556fb75444f28</id>
<content type='text'>
Link: https://lore.kernel.org/r/20250325122144.259256924@linuxfoundation.org
Tested-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Link: https://lore.kernel.org/r/20250326154346.820929475@linuxfoundation.org
Tested-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Tested-by: Hardik Garg &lt;hargar@linux.microsoft.com&gt;
Tested-by: Peter Schneider &lt;pschneider1968@googlemail.com&gt;
Tested-by: Ron Economos &lt;re@w6rz.net&gt;
Tested-by: Mark Brown &lt;broonie@kernel.org&gt;
Tested-by: Harshit Mogalapalli &lt;harshit.m.mogalapalli@oracle.com&gt;
Link: https://lore.kernel.org/r/20250328145011.672606157@linuxfoundation.org
Tested-by: Jon Hunter &lt;jonathanh@nvidia.com&gt;
Tested-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>netfilter: nft_counter: Use u64_stats_t for statistic.</title>
<updated>2025-03-28T20:59:57+00:00</updated>
<author>
<name>Sebastian Andrzej Siewior</name>
<email>bigeasy@linutronix.de</email>
</author>
<published>2024-08-20T07:54:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=fa81cb19f5b708921d4c2ca7bd5ef38f80f8d2c9'/>
<id>urn:sha1:fa81cb19f5b708921d4c2ca7bd5ef38f80f8d2c9</id>
<content type='text'>
commit 4a1d3acd6ea86075e77fcc1188c3fc372833ba73 upstream.

The nft_counter uses two s64 counters for statistics. Those two are
protected by a seqcount to ensure that the 64bit variable is always
properly seen during updates even on 32bit architectures where the store
is performed by two writes. A side effect is that the two counter (bytes
and packet) are written and read together in the same window.

This can be replaced with u64_stats_t. write_seqcount_begin()/ end() is
replaced with u64_stats_update_begin()/ end() and behaves the same way
as with seqcount_t on 32bit architectures. Additionally there is a
preempt_disable on PREEMPT_RT to ensure that a reader does not preempt a
writer.
On 64bit architectures the macros are removed and the reads happen
without any retries. This also means that the reader can observe one
counter (bytes) from before the update and the other counter (packets)
but that is okay since there is no requirement to have both counter from
the same update window.

Convert the statistic to u64_stats_t. There is one optimisation:
nft_counter_do_init() and nft_counter_clone() allocate a new per-CPU
counter and assign a value to it. During this assignment preemption is
disabled which is not needed because the counter is not yet exposed to
the system so there can not be another writer or reader. Therefore
disabling preemption is omitted and raw_cpu_ptr() is used to obtain a
pointer to a counter for the assignment.

Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Felix Moessbauer &lt;felix.moessbauer@siemens.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>wifi: iwlwifi: mvm: ensure offloading TID queue exists</title>
<updated>2025-03-28T20:59:57+00:00</updated>
<author>
<name>Benjamin Berg</name>
<email>benjamin.berg@intel.com</email>
</author>
<published>2024-02-18T17:51:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=35afffaddbe8d310dc61659da0b1a337b0d0addc'/>
<id>urn:sha1:35afffaddbe8d310dc61659da0b1a337b0d0addc</id>
<content type='text'>
commit 78f65fbf421a61894c14a1b91fe2fb4437b3fe5f upstream.

The resume code path assumes that the TX queue for the offloading TID
has been configured. At resume time it then tries to sync the write
pointer as it may have been updated by the firmware.

In the unusual event that no packets have been send on TID 0, the queue
will not have been allocated and this causes a crash. Fix this by
ensuring the queue exist at suspend time.

Signed-off-by: Benjamin Berg &lt;benjamin.berg@intel.com&gt;
Signed-off-by: Miri Korenblit &lt;miriam.rachel.korenblit@intel.com&gt;
Link: https://msgid.link/20240218194912.6632e6dc7b35.Ie6e6a7488c9c7d4529f13d48f752b5439d8ac3c4@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: Jianqi Ren &lt;jianqi.ren.cn@windriver.com&gt;
Signed-off-by: He Zhe &lt;zhe.he@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>wifi: iwlwifi: support BIOS override for 5G9 in CA also in LARI version 8</title>
<updated>2025-03-28T20:59:57+00:00</updated>
<author>
<name>Miri Korenblit</name>
<email>miriam.rachel.korenblit@intel.com</email>
</author>
<published>2024-12-26T15:44:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=fd82d29c4cfb4767167823ffac6825525c13d2cc'/>
<id>urn:sha1:fd82d29c4cfb4767167823ffac6825525c13d2cc</id>
<content type='text'>
commit b1e8102a4048003097c7054cbc00bbda91a5ced7 upstream.

Commit 6b3e87cc0ca5 ("iwlwifi: Add support for LARI_CONFIG_CHANGE_CMD
cmd v9")
added a few bits to iwl_lari_config_change_cmd::oem_unii4_allow_bitmap
if the FW has LARI version &gt;= 9.
But we also need to send those bits for version 8 if the FW is capable
of this feature (indicated with capability bits)
Add the FW capability bit, and set the additional bits in the cmd when
the version is 8 and the FW capability bit is set.

Signed-off-by: Miri Korenblit &lt;miriam.rachel.korenblit@intel.com&gt;
Reviewed-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Link: https://patch.msgid.link/20241226174257.dc5836f84514.I1e38f94465a36731034c94b9811de10cb6ee5921@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: Emmanuel Grumbach &lt;emmanuel.grumbach@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bnxt_en: Fix receive ring space parameters when XDP is active</title>
<updated>2025-03-28T20:59:57+00:00</updated>
<author>
<name>Shravya KN</name>
<email>shravya.k-n@broadcom.com</email>
</author>
<published>2024-11-22T22:45:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=7f306c651feab2f3689185f60b94e72b573255db'/>
<id>urn:sha1:7f306c651feab2f3689185f60b94e72b573255db</id>
<content type='text'>
commit 3051a77a09dfe3022aa012071346937fdf059033 upstream.

The MTU setting at the time an XDP multi-buffer is attached
determines whether the aggregation ring will be used and the
rx_skb_func handler.  This is done in bnxt_set_rx_skb_mode().

If the MTU is later changed, the aggregation ring setting may need
to be changed and it may become out-of-sync with the settings
initially done in bnxt_set_rx_skb_mode().  This may result in
random memory corruption and crashes as the HW may DMA data larger
than the allocated buffer size, such as:

BUG: kernel NULL pointer dereference, address: 00000000000003c0
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 17 PID: 0 Comm: swapper/17 Kdump: loaded Tainted: G S         OE      6.1.0-226bf9805506 #1
Hardware name: Wiwynn Delta Lake PVT BZA.02601.0150/Delta Lake-Class1, BIOS F0E_3A12 08/26/2021
RIP: 0010:bnxt_rx_pkt+0xe97/0x1ae0 [bnxt_en]
Code: 8b 95 70 ff ff ff 4c 8b 9d 48 ff ff ff 66 41 89 87 b4 00 00 00 e9 0b f7 ff ff 0f b7 43 0a 49 8b 95 a8 04 00 00 25 ff 0f 00 00 &lt;0f&gt; b7 14 42 48 c1 e2 06 49 03 95 a0 04 00 00 0f b6 42 33f
RSP: 0018:ffffa19f40cc0d18 EFLAGS: 00010202
RAX: 00000000000001e0 RBX: ffff8e2c805c6100 RCX: 00000000000007ff
RDX: 0000000000000000 RSI: ffff8e2c271ab990 RDI: ffff8e2c84f12380
RBP: ffffa19f40cc0e48 R08: 000000000001000d R09: 974ea2fcddfa4cbf
R10: 0000000000000000 R11: ffffa19f40cc0ff8 R12: ffff8e2c94b58980
R13: ffff8e2c952d6600 R14: 0000000000000016 R15: ffff8e2c271ab990
FS:  0000000000000000(0000) GS:ffff8e3b3f840000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000003c0 CR3: 0000000e8580a004 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 &lt;IRQ&gt;
 __bnxt_poll_work+0x1c2/0x3e0 [bnxt_en]

To address the issue, we now call bnxt_set_rx_skb_mode() within
bnxt_change_mtu() to properly set the AGG rings configuration and
update rx_skb_func based on the new MTU value.
Additionally, BNXT_FLAG_NO_AGG_RINGS is cleared at the beginning of
bnxt_set_rx_skb_mode() to make sure it gets set or cleared based on
the current MTU.

Fixes: 08450ea98ae9 ("bnxt_en: Fix max_mtu setting for multi-buf XDP")
Co-developed-by: Somnath Kotur &lt;somnath.kotur@broadcom.com&gt;
Signed-off-by: Somnath Kotur &lt;somnath.kotur@broadcom.com&gt;
Signed-off-by: Shravya KN &lt;shravya.k-n@broadcom.com&gt;
Signed-off-by: Michael Chan &lt;michael.chan@broadcom.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Jianqi Ren &lt;jianqi.ren.cn@windriver.com&gt;
Signed-off-by: He Zhe &lt;zhe.he@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>btrfs: make sure that WRITTEN is set on all metadata blocks</title>
<updated>2025-03-28T20:59:56+00:00</updated>
<author>
<name>Josef Bacik</name>
<email>josef@toxicpanda.com</email>
</author>
<published>2024-04-29T13:03:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=9dff3e36ea89e8003516841c27c45af562b6ef44'/>
<id>urn:sha1:9dff3e36ea89e8003516841c27c45af562b6ef44</id>
<content type='text'>
commit e03418abde871314e1a3a550f4c8afb7b89cb273 upstream.

We previously would call btrfs_check_leaf() if we had the check
integrity code enabled, which meant that we could only run the extended
leaf checks if we had WRITTEN set on the header flags.

This leaves a gap in our checking, because we could end up with
corruption on disk where WRITTEN isn't set on the leaf, and then the
extended leaf checks don't get run which we rely on to validate all of
the item pointers to make sure we don't access memory outside of the
extent buffer.

However, since 732fab95abe2 ("btrfs: check-integrity: remove
CONFIG_BTRFS_FS_CHECK_INTEGRITY option") we no longer call
btrfs_check_leaf() from btrfs_mark_buffer_dirty(), which means we only
ever call it on blocks that are being written out, and thus have WRITTEN
set, or that are being read in, which should have WRITTEN set.

Add checks to make sure we have WRITTEN set appropriately, and then make
sure __btrfs_check_leaf() always does the item checking.  This will
protect us from file systems that have been corrupted and no longer have
WRITTEN set on some of the blocks.

This was hit on a crafted image tweaking the WRITTEN bit and reported by
KASAN as out-of-bound access in the eb accessors. The example is a dir
item at the end of an eb.

  [2.042] BTRFS warning (device loop1): bad eb member start: ptr 0x3fff start 30572544 member offset 16410 size 2
  [2.040] general protection fault, probably for non-canonical address 0xe0009d1000000003: 0000 [#1] PREEMPT SMP KASAN NOPTI
  [2.537] KASAN: maybe wild-memory-access in range [0x0005088000000018-0x000508800000001f]
  [2.729] CPU: 0 PID: 2587 Comm: mount Not tainted 6.8.2 #1
  [2.729] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
  [2.621] RIP: 0010:btrfs_get_16+0x34b/0x6d0
  [2.621] RSP: 0018:ffff88810871fab8 EFLAGS: 00000206
  [2.621] RAX: 0000a11000000003 RBX: ffff888104ff8720 RCX: ffff88811b2288c0
  [2.621] RDX: dffffc0000000000 RSI: ffffffff81dd8aca RDI: ffff88810871f748
  [2.621] RBP: 000000000000401a R08: 0000000000000001 R09: ffffed10210e3ee9
  [2.621] R10: ffff88810871f74f R11: 205d323430333737 R12: 000000000000001a
  [2.621] R13: 000508800000001a R14: 1ffff110210e3f5d R15: ffffffff850011e8
  [2.621] FS:  00007f56ea275840(0000) GS:ffff88811b200000(0000) knlGS:0000000000000000
  [2.621] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [2.621] CR2: 00007febd13b75c0 CR3: 000000010bb50000 CR4: 00000000000006f0
  [2.621] Call Trace:
  [2.621]  &lt;TASK&gt;
  [2.621]  ? show_regs+0x74/0x80
  [2.621]  ? die_addr+0x46/0xc0
  [2.621]  ? exc_general_protection+0x161/0x2a0
  [2.621]  ? asm_exc_general_protection+0x26/0x30
  [2.621]  ? btrfs_get_16+0x33a/0x6d0
  [2.621]  ? btrfs_get_16+0x34b/0x6d0
  [2.621]  ? btrfs_get_16+0x33a/0x6d0
  [2.621]  ? __pfx_btrfs_get_16+0x10/0x10
  [2.621]  ? __pfx_mutex_unlock+0x10/0x10
  [2.621]  btrfs_match_dir_item_name+0x101/0x1a0
  [2.621]  btrfs_lookup_dir_item+0x1f3/0x280
  [2.621]  ? __pfx_btrfs_lookup_dir_item+0x10/0x10
  [2.621]  btrfs_get_tree+0xd25/0x1910

Reported-by: lei lu &lt;llfamsec@gmail.com&gt;
CC: stable@vger.kernel.org # 6.7+
Reviewed-by: Qu Wenruo &lt;wqu@suse.com&gt;
Signed-off-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
[ copy more details from report ]
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Jianqi Ren &lt;jianqi.ren.cn@windriver.com&gt;
Signed-off-by: He Zhe &lt;zhe.he@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>Revert "sched/core: Reduce cost of sched_move_task when config autogroup"</title>
<updated>2025-03-28T20:59:56+00:00</updated>
<author>
<name>Dietmar Eggemann</name>
<email>dietmar.eggemann@arm.com</email>
</author>
<published>2025-03-14T15:13:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=690597da35d940776068a4030839e1924341b4aa'/>
<id>urn:sha1:690597da35d940776068a4030839e1924341b4aa</id>
<content type='text'>
commit 76f970ce51c80f625eb6ddbb24e9cb51b977b598 upstream.

This reverts commit eff6c8ce8d4d7faef75f66614dd20bb50595d261.

Hazem reported a 30% drop in UnixBench spawn test with commit
eff6c8ce8d4d ("sched/core: Reduce cost of sched_move_task when config
autogroup") on a m6g.xlarge AWS EC2 instance with 4 vCPUs and 16 GiB RAM
(aarch64) (single level MC sched domain):

  https://lkml.kernel.org/r/20250205151026.13061-1-hagarhem@amazon.com

There is an early bail from sched_move_task() if p-&gt;sched_task_group is
equal to p's 'cpu cgroup' (sched_get_task_group()). E.g. both are
pointing to taskgroup '/user.slice/user-1000.slice/session-1.scope'
(Ubuntu '22.04.5 LTS').

So in:

  do_exit()

    sched_autogroup_exit_task()

      sched_move_task()

        if sched_get_task_group(p) == p-&gt;sched_task_group
          return

        /* p is enqueued */
        dequeue_task()              \
        sched_change_group()        |
          task_change_group_fair()  |
            detach_task_cfs_rq()    |                              (1)
            set_task_rq()           |
            attach_task_cfs_rq()    |
        enqueue_task()              /

(1) isn't called for p anymore.

Turns out that the regression is related to sgs-&gt;group_util in
group_is_overloaded() and group_has_capacity(). If (1) isn't called for
all the 'spawn' tasks then sgs-&gt;group_util is ~900 and
sgs-&gt;group_capacity = 1024 (single CPU sched domain) and this leads to
group_is_overloaded() returning true (2) and group_has_capacity() false
(3) much more often compared to the case when (1) is called.

I.e. there are much more cases of 'group_is_overloaded' and
'group_fully_busy' in WF_FORK wakeup sched_balance_find_dst_cpu() which
then returns much more often a CPU != smp_processor_id() (5).

This isn't good for these extremely short running tasks (FORK + EXIT)
and also involves calling sched_balance_find_dst_group_cpu() unnecessary
(single CPU sched domain).

Instead if (1) is called for 'p-&gt;flags &amp; PF_EXITING' then the path
(4),(6) is taken much more often.

  select_task_rq_fair(..., wake_flags = WF_FORK)

    cpu = smp_processor_id()

    new_cpu = sched_balance_find_dst_cpu(..., cpu, ...)

      group = sched_balance_find_dst_group(..., cpu)

        do {

          update_sg_wakeup_stats()

            sgs-&gt;group_type = group_classify()

              if group_is_overloaded()                             (2)
                return group_overloaded

              if !group_has_capacity()                             (3)
                return group_fully_busy

              return group_has_spare                               (4)

        } while group

        if local_sgs.group_type &gt; idlest_sgs.group_type
          return idlest                                            (5)

        case group_has_spare:

          if local_sgs.idle_cpus &gt;= idlest_sgs.idle_cpus
            return NULL                                            (6)

Unixbench Tests './Run -c 4 spawn' on:

(a) VM AWS instance (m7gd.16xlarge) with v6.13 ('maxcpus=4 nr_cpus=4')
    and Ubuntu 22.04.5 LTS (aarch64).

    Shell &amp; test run in '/user.slice/user-1000.slice/session-1.scope'.

    w/o patch	w/ patch
    21005	27120

(b) i7-13700K with tip/sched/core ('nosmt maxcpus=8 nr_cpus=8') and
    Ubuntu 22.04.5 LTS (x86_64).

    Shell &amp; test run in '/A'.

    w/o patch	w/ patch
    67675	88806

CONFIG_SCHED_AUTOGROUP=y &amp; /sys/proc/kernel/sched_autogroup_enabled equal
0 or 1.

Reported-by: Hazem Mohamed Abuelfotoh &lt;abuehaze@amazon.com&gt;
Signed-off-by: Dietmar Eggemann &lt;dietmar.eggemann@arm.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Reviewed-by: Vincent Guittot &lt;vincent.guittot@linaro.org&gt;
Tested-by: Hagar Hemdan &lt;hagarhem@amazon.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Link: https://lore.kernel.org/r/20250314151345.275739-1-dietmar.eggemann@arm.com
[Hagar: clean revert of eff6c8ce8dd7 to make it work on 6.6]
Signed-off-by: Hagar Hemdan &lt;hagarhem@amazon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>arm64: dts: rockchip: fix u2phy1_host status for NanoPi R4S</title>
<updated>2025-03-28T20:59:56+00:00</updated>
<author>
<name>Justin Klaassen</name>
<email>justin@tidylabs.net</email>
</author>
<published>2025-02-25T17:03:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=04cd1dc3df7f165e95f6fc20e6706cc6a25a948c'/>
<id>urn:sha1:04cd1dc3df7f165e95f6fc20e6706cc6a25a948c</id>
<content type='text'>
commit 38f4aa34a5f737ea8588dac320d884cc2e762c03 upstream.

The u2phy1_host should always have the same status as usb_host1_ehci
and usb_host1_ohci, otherwise the EHCI and OHCI drivers may be
initialized for a disabled usb port.

Per the NanoPi R4S schematic, the phy-supply for u2phy1_host is set to
the vdd_5v regulator.

Fixes: db792e9adbf8 ("rockchip: rk3399: Add support for FriendlyARM NanoPi R4S")
Cc: stable@vger.kernel.org
Signed-off-by: Justin Klaassen &lt;justin@tidylabs.net&gt;
Reviewed-by: Dragan Simic &lt;dsimic@manjaro.org&gt;
Link: https://lore.kernel.org/r/20250225170420.3898-1-justin@tidylabs.net
Signed-off-by: Heiko Stuebner &lt;heiko@sntech.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>KVM: arm64: Eagerly switch ZCR_EL{1,2}</title>
<updated>2025-03-28T20:59:56+00:00</updated>
<author>
<name>Mark Rutland</name>
<email>mark.rutland@arm.com</email>
</author>
<published>2025-03-21T00:16:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=7d566962942233c6c2c6f8b4d6b2f7f4a25b2076'/>
<id>urn:sha1:7d566962942233c6c2c6f8b4d6b2f7f4a25b2076</id>
<content type='text'>
[ Upstream commit 59419f10045bc955d2229819c7cf7a8b0b9c5b59 ]

In non-protected KVM modes, while the guest FPSIMD/SVE/SME state is live on the
CPU, the host's active SVE VL may differ from the guest's maximum SVE VL:

* For VHE hosts, when a VM uses NV, ZCR_EL2 contains a value constrained
  by the guest hypervisor, which may be less than or equal to that
  guest's maximum VL.

  Note: in this case the value of ZCR_EL1 is immaterial due to E2H.

* For nVHE/hVHE hosts, ZCR_EL1 contains a value written by the guest,
  which may be less than or greater than the guest's maximum VL.

  Note: in this case hyp code traps host SVE usage and lazily restores
  ZCR_EL2 to the host's maximum VL, which may be greater than the
  guest's maximum VL.

This can be the case between exiting a guest and kvm_arch_vcpu_put_fp().
If a softirq is taken during this period and the softirq handler tries
to use kernel-mode NEON, then the kernel will fail to save the guest's
FPSIMD/SVE state, and will pend a SIGKILL for the current thread.

This happens because kvm_arch_vcpu_ctxsync_fp() binds the guest's live
FPSIMD/SVE state with the guest's maximum SVE VL, and
fpsimd_save_user_state() verifies that the live SVE VL is as expected
before attempting to save the register state:

| if (WARN_ON(sve_get_vl() != vl)) {
|         force_signal_inject(SIGKILL, SI_KERNEL, 0, 0);
|         return;
| }

Fix this and make this a bit easier to reason about by always eagerly
switching ZCR_EL{1,2} at hyp during guest&lt;-&gt;host transitions. With this
happening, there's no need to trap host SVE usage, and the nVHE/nVHE
__deactivate_cptr_traps() logic can be simplified to enable host access
to all present FPSIMD/SVE/SME features.

In protected nVHE/hVHE modes, the host's state is always saved/restored
by hyp, and the guest's state is saved prior to exit to the host, so
from the host's PoV the guest never has live FPSIMD/SVE/SME state, and
the host's ZCR_EL1 is never clobbered by hyp.

Fixes: 8c8010d69c132273 ("KVM: arm64: Save/restore SVE state for nVHE")
Fixes: 2e3cf82063a00ea0 ("KVM: arm64: nv: Ensure correct VL is loaded before saving SVE state")
Signed-off-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Reviewed-by: Mark Brown &lt;broonie@kernel.org&gt;
Tested-by: Mark Brown &lt;broonie@kernel.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Fuad Tabba &lt;tabba@google.com&gt;
Cc: Marc Zyngier &lt;maz@kernel.org&gt;
Cc: Oliver Upton &lt;oliver.upton@linux.dev&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Reviewed-by: Oliver Upton &lt;oliver.upton@linux.dev&gt;
Link: https://lore.kernel.org/r/20250210195226.1215254-9-mark.rutland@arm.com
Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
[ v6.6 lacks pKVM saving of host SVE state, pull in discovery of maximum
  host VL separately -- broonie ]
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>KVM: arm64: Mark some header functions as inline</title>
<updated>2025-03-28T20:59:56+00:00</updated>
<author>
<name>Mark Rutland</name>
<email>mark.rutland@arm.com</email>
</author>
<published>2025-03-21T00:16:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=93074abedecb522795f91b143a20a0d019224048'/>
<id>urn:sha1:93074abedecb522795f91b143a20a0d019224048</id>
<content type='text'>
[ Upstream commit f9dd00de1e53a47763dfad601635d18542c3836d ]

The shared hyp switch header has a number of static functions which
might not be used by all files that include the header, and when unused
they will provoke compiler warnings, e.g.

| In file included from arch/arm64/kvm/hyp/nvhe/hyp-main.c:8:
| ./arch/arm64/kvm/hyp/include/hyp/switch.h:703:13: warning: 'kvm_hyp_handle_dabt_low' defined but not used [-Wunused-function]
|   703 | static bool kvm_hyp_handle_dabt_low(struct kvm_vcpu *vcpu, u64 *exit_code)
|       |             ^~~~~~~~~~~~~~~~~~~~~~~
| ./arch/arm64/kvm/hyp/include/hyp/switch.h:682:13: warning: 'kvm_hyp_handle_cp15_32' defined but not used [-Wunused-function]
|   682 | static bool kvm_hyp_handle_cp15_32(struct kvm_vcpu *vcpu, u64 *exit_code)
|       |             ^~~~~~~~~~~~~~~~~~~~~~
| ./arch/arm64/kvm/hyp/include/hyp/switch.h:662:13: warning: 'kvm_hyp_handle_sysreg' defined but not used [-Wunused-function]
|   662 | static bool kvm_hyp_handle_sysreg(struct kvm_vcpu *vcpu, u64 *exit_code)
|       |             ^~~~~~~~~~~~~~~~~~~~~
| ./arch/arm64/kvm/hyp/include/hyp/switch.h:458:13: warning: 'kvm_hyp_handle_fpsimd' defined but not used [-Wunused-function]
|   458 | static bool kvm_hyp_handle_fpsimd(struct kvm_vcpu *vcpu, u64 *exit_code)
|       |             ^~~~~~~~~~~~~~~~~~~~~
| ./arch/arm64/kvm/hyp/include/hyp/switch.h:329:13: warning: 'kvm_hyp_handle_mops' defined but not used [-Wunused-function]
|   329 | static bool kvm_hyp_handle_mops(struct kvm_vcpu *vcpu, u64 *exit_code)
|       |             ^~~~~~~~~~~~~~~~~~~

Mark these functions as 'inline' to suppress this warning. This
shouldn't result in any functional change.

At the same time, avoid the use of __alias() in the header and alias
kvm_hyp_handle_iabt_low() and kvm_hyp_handle_watchpt_low() to
kvm_hyp_handle_memory_fault() using CPP, matching the style in the rest
of the kernel. For consistency, kvm_hyp_handle_memory_fault() is also
marked as 'inline'.

Signed-off-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Reviewed-by: Mark Brown &lt;broonie@kernel.org&gt;
Tested-by: Mark Brown &lt;broonie@kernel.org&gt;
Acked-by: Will Deacon &lt;will@kernel.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Fuad Tabba &lt;tabba@google.com&gt;
Cc: Marc Zyngier &lt;maz@kernel.org&gt;
Cc: Oliver Upton &lt;oliver.upton@linux.dev&gt;
Reviewed-by: Oliver Upton &lt;oliver.upton@linux.dev&gt;
Link: https://lore.kernel.org/r/20250210195226.1215254-8-mark.rutland@arm.com
Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
</feed>
