<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include/linux, branch v6.1.121</title>
<subtitle>Linux Kernel
</subtitle>
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<updated>2024-12-19T17:08:59Z</updated>
<entry>
<title>x86/static-call: fix 32-bit build</title>
<updated>2024-12-19T17:08:59Z</updated>
<author>
<name>Juergen Gross</name>
<email>jgross@suse.com</email>
</author>
<published>2024-12-18T08:02:28Z</published>
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<content type='text'>
commit 349f0086ba8b2a169877d21ff15a4d9da3a60054 upstream.

In 32-bit x86 builds CONFIG_STATIC_CALL_INLINE isn't set, leading to
static_call_initialized not being available.

Define it as "0" in that case.

Reported-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Fixes: 0ef8047b737d ("x86/static-call: provide a way to do very early static-call updates")
Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>x86/static-call: provide a way to do very early static-call updates</title>
<updated>2024-12-19T17:08:58Z</updated>
<author>
<name>Juergen Gross</name>
<email>jgross@suse.com</email>
</author>
<published>2024-11-29T15:15:54Z</published>
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<id>urn:sha1:f8b1f5472b19e29439d58dc52cfb67cfeac18770</id>
<content type='text'>
commit 0ef8047b737d7480a5d4c46d956e97c190f13050 upstream.

Add static_call_update_early() for updating static-call targets in
very early boot.

This will be needed for support of Xen guest type specific hypercall
functions.

This is part of XSA-466 / CVE-2024-53241.

Reported-by: Andrew Cooper &lt;andrew.cooper3@citrix.com&gt;
Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Co-developed-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Co-developed-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: mscc: ocelot: be resilient to loss of PTP packets during transmission</title>
<updated>2024-12-19T17:08:54Z</updated>
<author>
<name>Vladimir Oltean</name>
<email>vladimir.oltean@nxp.com</email>
</author>
<published>2024-12-05T14:55:18Z</published>
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<id>urn:sha1:da0732ef2abff267e46d4bdb00c7bf4b881e2820</id>
<content type='text'>
[ Upstream commit b454abfab52543c44b581afc807b9f97fc1e7a3a ]

The Felix DSA driver presents unique challenges that make the simplistic
ocelot PTP TX timestamping procedure unreliable: any transmitted packet
may be lost in hardware before it ever leaves our local system.

This may happen because there is congestion on the DSA conduit, the
switch CPU port or even user port (Qdiscs like taprio may delay packets
indefinitely by design).

The technical problem is that the kernel, i.e. ocelot_port_add_txtstamp_skb(),
runs out of timestamp IDs eventually, because it never detects that
packets are lost, and keeps the IDs of the lost packets on hold
indefinitely. The manifestation of the issue once the entire timestamp
ID range becomes busy looks like this in dmesg:

mscc_felix 0000:00:00.5: port 0 delivering skb without TX timestamp
mscc_felix 0000:00:00.5: port 1 delivering skb without TX timestamp

At the surface level, we need a timeout timer so that the kernel knows a
timestamp ID is available again. But there is a deeper problem with the
implementation, which is the monotonically increasing ocelot_port-&gt;ts_id.
In the presence of packet loss, it will be impossible to detect that and
reuse one of the holes created in the range of free timestamp IDs.

What we actually need is a bitmap of 63 timestamp IDs tracking which one
is available. That is able to use up holes caused by packet loss, but
also gives us a unique opportunity to not implement an actual timer_list
for the timeout timer (very complicated in terms of locking).

We could only declare a timestamp ID stale on demand (lazily), aka when
there's no other timestamp ID available. There are pros and cons to this
approach: the implementation is much more simple than per-packet timers
would be, but most of the stale packets would be quasi-leaked - not
really leaked, but blocked in driver memory, since this algorithm sees
no reason to free them.

An improved technique would be to check for stale timestamp IDs every
time we allocate a new one. Assuming a constant flux of PTP packets,
this avoids stale packets being blocked in memory, but of course,
packets lost at the end of the flux are still blocked until the flux
resumes (nobody left to kick them out).

Since implementing per-packet timers is way too complicated, this should
be good enough.

Testing procedure:

Persistently block traffic class 5 and try to run PTP on it:
$ tc qdisc replace dev swp3 parent root taprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
	base-time 0 sched-entry S 0xdf 100000 flags 0x2
[  126.948141] mscc_felix 0000:00:00.5: port 3 tc 5 min gate length 0 ns not enough for max frame size 1526 at 1000 Mbps, dropping frames over 1 octets including FCS
$ ptp4l -i swp3 -2 -P -m --socket_priority 5 --fault_reset_interval ASAP --logSyncInterval -3
ptp4l[70.351]: port 1 (swp3): INITIALIZING to LISTENING on INIT_COMPLETE
ptp4l[70.354]: port 0 (/var/run/ptp4l): INITIALIZING to LISTENING on INIT_COMPLETE
ptp4l[70.358]: port 0 (/var/run/ptp4lro): INITIALIZING to LISTENING on INIT_COMPLETE
[   70.394583] mscc_felix 0000:00:00.5: port 3 timestamp id 0
ptp4l[70.406]: timed out while polling for tx timestamp
ptp4l[70.406]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it
ptp4l[70.406]: port 1 (swp3): send peer delay response failed
ptp4l[70.407]: port 1 (swp3): clearing fault immediately
ptp4l[70.952]: port 1 (swp3): new foreign master d858d7.fffe.00ca6d-1
[   71.394858] mscc_felix 0000:00:00.5: port 3 timestamp id 1
ptp4l[71.400]: timed out while polling for tx timestamp
ptp4l[71.400]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it
ptp4l[71.401]: port 1 (swp3): send peer delay response failed
ptp4l[71.401]: port 1 (swp3): clearing fault immediately
[   72.393616] mscc_felix 0000:00:00.5: port 3 timestamp id 2
ptp4l[72.401]: timed out while polling for tx timestamp
ptp4l[72.402]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it
ptp4l[72.402]: port 1 (swp3): send peer delay response failed
ptp4l[72.402]: port 1 (swp3): clearing fault immediately
ptp4l[72.952]: port 1 (swp3): new foreign master d858d7.fffe.00ca6d-1
[   73.395291] mscc_felix 0000:00:00.5: port 3 timestamp id 3
ptp4l[73.400]: timed out while polling for tx timestamp
ptp4l[73.400]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it
ptp4l[73.400]: port 1 (swp3): send peer delay response failed
ptp4l[73.400]: port 1 (swp3): clearing fault immediately
[   74.394282] mscc_felix 0000:00:00.5: port 3 timestamp id 4
ptp4l[74.400]: timed out while polling for tx timestamp
ptp4l[74.401]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it
ptp4l[74.401]: port 1 (swp3): send peer delay response failed
ptp4l[74.401]: port 1 (swp3): clearing fault immediately
ptp4l[74.953]: port 1 (swp3): new foreign master d858d7.fffe.00ca6d-1
[   75.396830] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 0 which seems lost
[   75.405760] mscc_felix 0000:00:00.5: port 3 timestamp id 0
ptp4l[75.410]: timed out while polling for tx timestamp
ptp4l[75.411]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it
ptp4l[75.411]: port 1 (swp3): send peer delay response failed
ptp4l[75.411]: port 1 (swp3): clearing fault immediately
(...)

Remove the blocking condition and see that the port recovers:
$ same tc command as above, but use "sched-entry S 0xff" instead
$ same ptp4l command as above
ptp4l[99.489]: port 1 (swp3): INITIALIZING to LISTENING on INIT_COMPLETE
ptp4l[99.490]: port 0 (/var/run/ptp4l): INITIALIZING to LISTENING on INIT_COMPLETE
ptp4l[99.492]: port 0 (/var/run/ptp4lro): INITIALIZING to LISTENING on INIT_COMPLETE
[  100.403768] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 0 which seems lost
[  100.412545] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 1 which seems lost
[  100.421283] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 2 which seems lost
[  100.430015] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 3 which seems lost
[  100.438744] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 4 which seems lost
[  100.447470] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  100.505919] mscc_felix 0000:00:00.5: port 3 timestamp id 0
ptp4l[100.963]: port 1 (swp3): new foreign master d858d7.fffe.00ca6d-1
[  101.405077] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  101.507953] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  102.405405] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  102.509391] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  103.406003] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  103.510011] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  104.405601] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  104.510624] mscc_felix 0000:00:00.5: port 3 timestamp id 0
ptp4l[104.965]: selected best master clock d858d7.fffe.00ca6d
ptp4l[104.966]: port 1 (swp3): assuming the grand master role
ptp4l[104.967]: port 1 (swp3): LISTENING to GRAND_MASTER on RS_GRAND_MASTER
[  105.106201] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  105.232420] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  105.359001] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  105.405500] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  105.485356] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  105.511220] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  105.610938] mscc_felix 0000:00:00.5: port 3 timestamp id 0
[  105.737237] mscc_felix 0000:00:00.5: port 3 timestamp id 0
(...)

Notice that in this new usage pattern, a non-congested port should
basically use timestamp ID 0 all the time, progressing to higher numbers
only if there are unacknowledged timestamps in flight. Compare this to
the old usage, where the timestamp ID used to monotonically increase
modulo OCELOT_MAX_PTP_ID.

In terms of implementation, this simplifies the bookkeeping of the
ocelot_port :: ts_id and ptp_skbs_in_flight. Since we need to traverse
the list of two-step timestampable skbs for each new packet anyway, the
information can already be computed and does not need to be stored.
Also, ocelot_port-&gt;tx_skbs is always accessed under the switch-wide
ocelot-&gt;ts_id_lock IRQ-unsafe spinlock, so we don't need the skb queue's
lock and can use the unlocked primitives safely.

This problem was actually detected using the tc-taprio offload, and is
causing trouble in TSN scenarios, which Felix (NXP LS1028A / VSC9959)
supports but Ocelot (VSC7514) does not. Thus, I've selected the commit
to blame as the one adding initial timestamping support for the Felix
switch.

Fixes: c0bcf537667c ("net: dsa: ocelot: add hardware timestamping support for Felix")
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Link: https://patch.msgid.link/20241205145519.1236778-5-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ptp: kvm: Use decrypted memory in confidential guest on x86</title>
<updated>2024-12-19T17:08:53Z</updated>
<author>
<name>Jeremi Piotrowski</name>
<email>jpiotrowski@linux.microsoft.com</email>
</author>
<published>2023-03-08T15:05:31Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=5ea817f40dbb78dc8fe0b073b2d069eb721e32aa'/>
<id>urn:sha1:5ea817f40dbb78dc8fe0b073b2d069eb721e32aa</id>
<content type='text'>
[ Upstream commit 6365ba64b4dbe8b59ddaeaa724b281f3787715d5 ]

KVM_HC_CLOCK_PAIRING currently fails inside SEV-SNP guests because the
guest passes an address to static data to the host. In confidential
computing the host can't access arbitrary guest memory so handling the
hypercall runs into an "rmpfault". To make the hypercall work, the guest
needs to explicitly mark the memory as decrypted. Do that in
kvm_arch_ptp_init(), but retain the previous behavior for
non-confidential guests to save us from having to allocate memory.

Add a new arch-specific function (kvm_arch_ptp_exit()) to free the
allocation and mark the memory as encrypted again.

Signed-off-by: Jeremi Piotrowski &lt;jpiotrowski@linux.microsoft.com&gt;
Link: https://lore.kernel.org/r/20230308150531.477741-1-jpiotrowski@linux.microsoft.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Stable-dep-of: 5e7aa97c7acf ("ptp: kvm: x86: Return EOPNOTSUPP instead of ENODEV from kvm_arch_ptp_init()")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>PM / devfreq: Fix build issues with devfreq disabled</title>
<updated>2024-12-14T18:54:55Z</updated>
<author>
<name>Rob Clark</name>
<email>robdclark@chromium.org</email>
</author>
<published>2023-01-23T15:37:45Z</published>
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<id>urn:sha1:5446585e424248859fcf936a354278d1f6f95038</id>
<content type='text'>
commit dbd7a2a941b8cbf9e5f79a777ed9fe0090eebb61 upstream.

The existing no-op shims for when PM_DEVFREQ (or an individual governor)
only do half the job.  The governor specific config/tuning structs need
to be available to avoid compile errors in drivers using devfreq.

Fixes: 6563f60f14cb ("drm/msm/gpu: Add devfreq tuning debugfs")
Signed-off-by: Rob Clark &lt;robdclark@chromium.org&gt;
Acked-by: MyungJoo Ham &lt;myungjoo.ham@samsung.com&gt;
Acked-by: Chanwoo Choi &lt;cw00.choi@samsung.com&gt;
Patchwork: https://patchwork.freedesktop.org/patch/519801/
Link: https://lore.kernel.org/r/20230123153745.3185032-1-robdclark@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: Move {l,t,d}stats allocation to core and convert veth &amp; vrf</title>
<updated>2024-12-14T18:54:54Z</updated>
<author>
<name>Daniel Borkmann</name>
<email>daniel@iogearbox.net</email>
</author>
<published>2024-12-06T15:34:01Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=877c81faf00548720a7f436538865070a5d63c96'/>
<id>urn:sha1:877c81faf00548720a7f436538865070a5d63c96</id>
<content type='text'>
[ Upstream commit 34d21de99cea9cb17967874313e5b0262527833c ]

Move {l,t,d}stats allocation to the core and let netdevs pick the stats
type they need. That way the driver doesn't have to bother with error
handling (allocation failure checking, making sure free happens in the
right spot, etc) - all happening in the core.

Co-developed-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Nikolay Aleksandrov &lt;razor@blackwall.org&gt;
Cc: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20231114004220.6495-3-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau &lt;martin.lau@kernel.org&gt;
Stable-dep-of: 024ee930cb3c ("bpf: Fix dev's rx stats for bpf_redirect_peer traffic")
[ Note: Simplified vrf bits to reduce patch given unrelated to the fix ]
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: Fix helper writes to read-only maps</title>
<updated>2024-12-14T18:54:53Z</updated>
<author>
<name>Daniel Borkmann</name>
<email>daniel@iogearbox.net</email>
</author>
<published>2024-09-13T19:17:48Z</published>
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<id>urn:sha1:988e55abcf7fdb8fc9a76a7cf3f4e939a4d4fb3a</id>
<content type='text'>
commit 32556ce93bc45c730829083cb60f95a2728ea48b upstream.

Lonial found an issue that despite user- and BPF-side frozen BPF map
(like in case of .rodata), it was still possible to write into it from
a BPF program side through specific helpers having ARG_PTR_TO_{LONG,INT}
as arguments.

In check_func_arg() when the argument is as mentioned, the meta-&gt;raw_mode
is never set. Later, check_helper_mem_access(), under the case of
PTR_TO_MAP_VALUE as register base type, it assumes BPF_READ for the
subsequent call to check_map_access_type() and given the BPF map is
read-only it succeeds.

The helpers really need to be annotated as ARG_PTR_TO_{LONG,INT} | MEM_UNINIT
when results are written into them as opposed to read out of them. The
latter indicates that it's okay to pass a pointer to uninitialized memory
as the memory is written to anyway.

However, ARG_PTR_TO_{LONG,INT} is a special case of ARG_PTR_TO_FIXED_SIZE_MEM
just with additional alignment requirement. So it is better to just get
rid of the ARG_PTR_TO_{LONG,INT} special cases altogether and reuse the
fixed size memory types. For this, add MEM_ALIGNED to additionally ensure
alignment given these helpers write directly into the args via *&lt;ptr&gt; = val.
The .arg*_size has been initialized reflecting the actual sizeof(*&lt;ptr&gt;).

MEM_ALIGNED can only be used in combination with MEM_FIXED_SIZE annotated
argument types, since in !MEM_FIXED_SIZE cases the verifier does not know
the buffer size a priori and therefore cannot blindly write *&lt;ptr&gt; = val.

Fixes: 57c3bb725a3d ("bpf: Introduce ARG_PTR_TO_{INT,LONG} arg types")
Reported-by: Lonial Con &lt;kongln9170@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: Andrii Nakryiko &lt;andrii@kernel.org&gt;
Acked-by: Shung-Hsi Yu &lt;shung-hsi.yu@suse.com&gt;
Link: https://lore.kernel.org/r/20240913191754.13290-3-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
[ Resolve merge conflict in include/linux/bpf.h and merge conflict in
  kernel/bpf/verifier.c.]
Signed-off-by: Bin Lan &lt;bin.lan.cn@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>arm64: smccc: Remove broken support for SMCCCv1.3 SVE discard hint</title>
<updated>2024-12-14T18:54:53Z</updated>
<author>
<name>Mark Rutland</name>
<email>mark.rutland@arm.com</email>
</author>
<published>2024-11-06T16:04:48Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=bfcaffd4cc2d61ecb0571c5baf127c4089978ad4'/>
<id>urn:sha1:bfcaffd4cc2d61ecb0571c5baf127c4089978ad4</id>
<content type='text'>
commit 8c462d56487e3abdbf8a61cedfe7c795a54f4a78 upstream.

SMCCCv1.3 added a hint bit which callers can set in an SMCCC function ID
(AKA "FID") to indicate that it is acceptable for the SMCCC
implementation to discard SVE and/or SME state over a specific SMCCC
call. The kernel support for using this hint is broken and SMCCC calls
may clobber the SVE and/or SME state of arbitrary tasks, though FPSIMD
state is unaffected.

The kernel support is intended to use the hint when there is no SVE or
SME state to save, and to do this it checks whether TIF_FOREIGN_FPSTATE
is set or TIF_SVE is clear in assembly code:

|        ldr     &lt;flags&gt;, [&lt;current_task&gt;, #TSK_TI_FLAGS]
|        tbnz    &lt;flags&gt;, #TIF_FOREIGN_FPSTATE, 1f   // Any live FP state?
|        tbnz    &lt;flags&gt;, #TIF_SVE, 2f               // Does that state include SVE?
|
| 1:     orr     &lt;fid&gt;, &lt;fid&gt;, ARM_SMCCC_1_3_SVE_HINT
| 2:
|        &lt;&lt; SMCCC call using FID &gt;&gt;

This is not safe as-is:

(1) SMCCC calls can be made in a preemptible context and preemption can
    result in TIF_FOREIGN_FPSTATE being set or cleared at arbitrary
    points in time. Thus checking for TIF_FOREIGN_FPSTATE provides no
    guarantee.

(2) TIF_FOREIGN_FPSTATE only indicates that the live FP/SVE/SME state in
    the CPU does not belong to the current task, and does not indicate
    that clobbering this state is acceptable.

    When the live CPU state is clobbered it is necessary to update
    fpsimd_last_state.st to ensure that a subsequent context switch will
    reload FP/SVE/SME state from memory rather than consuming the
    clobbered state. This and the SMCCC call itself must happen in a
    critical section with preemption disabled to avoid races.

(3) Live SVE/SME state can exist with TIF_SVE clear (e.g. with only
    TIF_SME set), and checking TIF_SVE alone is insufficient.

Remove the broken support for the SMCCCv1.3 SVE saving hint. This is
effectively a revert of commits:

* cfa7ff959a78 ("arm64: smccc: Support SMCCC v1.3 SVE register saving hint")
* a7c3acca5380 ("arm64: smccc: Save lr before calling __arm_smccc_sve_check()")

... leaving behind the ARM_SMCCC_VERSION_1_3 and ARM_SMCCC_1_3_SVE_HINT
definitions, since these are simply definitions from the SMCCC
specification, and the latter is used in KVM via ARM_SMCCC_CALL_HINTS.

If we want to bring this back in future, we'll probably want to handle
this logic in C where we can use all the usual FPSIMD/SVE/SME helper
functions, and that'll likely require some rework of the SMCCC code
and/or its callers.

Fixes: cfa7ff959a78 ("arm64: smccc: Support SMCCC v1.3 SVE register saving hint")
Signed-off-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Marc Zyngier &lt;maz@kernel.org&gt;
Cc: Mark Brown &lt;broonie@kernel.org&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: stable@vger.kernel.org
Reviewed-by: Mark Brown &lt;broonie@kernel.org&gt;
Link: https://lore.kernel.org/r/20241106160448.2712997-1-mark.rutland@arm.com
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
[ Mark: fix conflicts in &lt;linux/arm-smccc.h&gt; ]
Signed-off-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle</title>
<updated>2024-12-14T18:54:49Z</updated>
<author>
<name>Parker Newman</name>
<email>pnewman@connecttech.com</email>
</author>
<published>2024-10-02T15:12:33Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=80be263f3f453b6e8efc2e5809347dc9ae7c3e29'/>
<id>urn:sha1:80be263f3f453b6e8efc2e5809347dc9ae7c3e29</id>
<content type='text'>
[ Upstream commit 7738a7ab9d12c5371ed97114ee2132d4512e9fd5 ]

Add a quirk similar to eeprom_93xx46 to add an extra clock cycle before
reading data from the EEPROM.

The 93Cx6 family of EEPROMs output a "dummy 0 bit" between the writing
of the op-code/address from the host to the EEPROM and the reading of
the actual data from the EEPROM.

More info can be found on page 6 of the AT93C46 datasheet (linked below).
Similar notes are found in other 93xx6 datasheets.

In summary the read operation for a 93Cx6 EEPROM is:
Write to EEPROM:	110[A5-A0]	(9 bits)
Read from EEPROM:	0[D15-D0]	(17 bits)

Where:
	110 is the start bit and READ OpCode
	[A5-A0] is the address to read from
	0 is a "dummy bit" preceding the actual data
	[D15-D0] is the actual data.

Looking at the READ timing diagrams in the 93Cx6 datasheets the dummy
bit should be clocked out on the last address bit clock cycle meaning it
should be discarded naturally.

However, depending on the hardware configuration sometimes this dummy
bit is not discarded. This is the case with Exar PCI UARTs which require
an extra clock cycle between sending the address and reading the data.

Datasheet: https://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-5193-SEEPROM-AT93C46D-Datasheet.pdf
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Signed-off-by: Parker Newman &lt;pnewman@connecttech.com&gt;
Link: https://lore.kernel.org/r/0f23973efefccd2544705a0480b4ad4c2353e407.1727880931.git.pnewman@connecttech.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>PCI: Detect and trust built-in Thunderbolt chips</title>
<updated>2024-12-14T18:54:47Z</updated>
<author>
<name>Esther Shimanovich</name>
<email>eshimanovich@chromium.org</email>
</author>
<published>2024-09-10T17:57:45Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2dcaa24a007e3320ac60335455865ef0b01034cd'/>
<id>urn:sha1:2dcaa24a007e3320ac60335455865ef0b01034cd</id>
<content type='text'>
[ Upstream commit 3b96b895127b7c0aed63d82c974b46340e8466c1 ]

Some computers with CPUs that lack Thunderbolt features use discrete
Thunderbolt chips to add Thunderbolt functionality. These Thunderbolt
chips are located within the chassis; between the Root Port labeled
ExternalFacingPort and the USB-C port.

These Thunderbolt PCIe devices should be labeled as fixed and trusted, as
they are built into the computer. Otherwise, security policies that rely on
those flags may have unintended results, such as preventing USB-C ports
from enumerating.

Detect the above scenario through the process of elimination.

  1) Integrated Thunderbolt host controllers already have Thunderbolt
     implemented, so anything outside their external facing Root Port is
     removable and untrusted.

     Detect them using the following properties:

       - Most integrated host controllers have the "usb4-host-interface"
         ACPI property, as described here:

         https://learn.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#mapping-native-protocols-pcie-displayport-tunneled-through-usb4-to-usb4-host-routers

       - Integrated Thunderbolt PCIe Root Ports before Alder Lake do not
         have the "usb4-host-interface" ACPI property. Identify those by
         their PCI IDs instead.

  2) If a Root Port does not have integrated Thunderbolt capabilities, but
     has the "ExternalFacingPort" ACPI property, that means the
     manufacturer has opted to use a discrete Thunderbolt host controller
     that is built into the computer.

     This host controller can be identified by virtue of being located
     directly below an external-facing Root Port that lacks integrated
     Thunderbolt. Label it as trusted and fixed.

     Everything downstream from it is untrusted and removable.

The "ExternalFacingPort" ACPI property is described here:
https://learn.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-externally-exposed-pcie-root-ports

Link: https://lore.kernel.org/r/20240910-trust-tbt-fix-v5-1-7a7a42a5f496@chromium.org
Suggested-by: Mika Westerberg &lt;mika.westerberg@linux.intel.com&gt;
Signed-off-by: Esther Shimanovich &lt;eshimanovich@chromium.org&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Tested-by: Mika Westerberg &lt;mika.westerberg@linux.intel.com&gt;
Tested-by: Mario Limonciello &lt;mario.limonciello@amd.com&gt;
Reviewed-by: Mika Westerberg &lt;mika.westerberg@linux.intel.com&gt;
Reviewed-by: Mario Limonciello &lt;mario.limonciello@amd.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
