<feed xmlns='http://www.w3.org/2005/Atom'>
<title>lwn.git/net/iucv, branch docs-6.9</title>
<subtitle>Linux kernel documentation tree maintained by Jonathan Corbet</subtitle>
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<updated>2023-12-29T07:46:38+00:00</updated>
<entry>
<title>iucv: make iucv_bus const</title>
<updated>2023-12-29T07:46:38+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2023-12-20T07:41:18+00:00</published>
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<id>urn:sha1:f732ba4ac9f3626e235cc33a4f1756f17884dd32</id>
<content type='text'>
Now that the driver core can properly handle constant struct bus_type,
move the iucv_bus variable to be a constant structure as well, placing
it into read-only memory which can not be modified at runtime.

Cc: Wenjia Zhang &lt;wenjia@linux.ibm.com&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Jakub Kicinski &lt;kuba@kernel.org&gt;
Cc: Paolo Abeni &lt;pabeni@redhat.com&gt;
Cc: linux-s390@vger.kernel.org
Cc: netdev@vger.kernel.org
Acked-by: Alexandra Winter &lt;wintera@linux.ibm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>s390: use control register bit defines</title>
<updated>2023-09-19T11:26:57+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2023-09-11T19:40:13+00:00</published>
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<id>urn:sha1:99441a38c391b1115e405d1f47ede237fca37f1b</id>
<content type='text'>
Use control register bit defines instead of plain numbers where
possible.

Reviewed-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>s390/ctlreg: add local and system prefix to some functions</title>
<updated>2023-09-19T11:26:56+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2023-09-11T19:39:58+00:00</published>
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<id>urn:sha1:8d5e98f8d6b11dd0e61323ece3b7ccceea55c281</id>
<content type='text'>
Add local and system prefix to some functions to clarify they change
control register contents on either the local CPU or the on all CPUs.

This results in the following API:

Two defines which load and save multiple control registers.
The defines correlate with the following C prototypes:

void __local_ctl_load(unsigned long *, unsigned int cr_low, unsigned int cr_high);
void __local_ctl_store(unsigned long *, unsigned int cr_low, unsigned int cr_high);

Two functions which locally set or clear one bit for a specified
control register:

void local_ctl_set_bit(unsigned int cr, unsigned int bit);
void local_ctl_clear_bit(unsigned int cr, unsigned int bit);

Two functions which set or clear one bit for a specified control
register on all CPUs:

void system_ctl_set_bit(unsigned int cr, unsigned int bit);
void system_ctl_clear_bit(unsigend int cr, unsigned int bit);

Reviewed-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
</content>
</entry>
<entry>
<title>net/iucv: Fix size of interrupt data</title>
<updated>2023-03-17T00:34:40+00:00</updated>
<author>
<name>Alexandra Winter</name>
<email>wintera@linux.ibm.com</email>
</author>
<published>2023-03-15T13:14:35+00:00</published>
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<id>urn:sha1:3d87debb8ed2649608ff432699e7c961c0c6f03b</id>
<content type='text'>
iucv_irq_data needs to be 4 bytes larger.
These bytes are not used by the iucv module, but written by
the z/VM hypervisor in case a CPU is deconfigured.

Reported as:
BUG dma-kmalloc-64 (Not tainted): kmalloc Redzone overwritten
-----------------------------------------------------------------------------
0x0000000000400564-0x0000000000400567 @offset=1380. First byte 0x80 instead of 0xcc
Allocated in iucv_cpu_prepare+0x44/0xd0 age=167839 cpu=2 pid=1
__kmem_cache_alloc_node+0x166/0x450
kmalloc_node_trace+0x3a/0x70
iucv_cpu_prepare+0x44/0xd0
cpuhp_invoke_callback+0x156/0x2f0
cpuhp_issue_call+0xf0/0x298
__cpuhp_setup_state_cpuslocked+0x136/0x338
__cpuhp_setup_state+0xf4/0x288
iucv_init+0xf4/0x280
do_one_initcall+0x78/0x390
do_initcalls+0x11a/0x140
kernel_init_freeable+0x25e/0x2a0
kernel_init+0x2e/0x170
__ret_from_fork+0x3c/0x58
ret_from_fork+0xa/0x40
Freed in iucv_init+0x92/0x280 age=167839 cpu=2 pid=1
__kmem_cache_free+0x308/0x358
iucv_init+0x92/0x280
do_one_initcall+0x78/0x390
do_initcalls+0x11a/0x140
kernel_init_freeable+0x25e/0x2a0
kernel_init+0x2e/0x170
__ret_from_fork+0x3c/0x58
ret_from_fork+0xa/0x40
Slab 0x0000037200010000 objects=32 used=30 fp=0x0000000000400640 flags=0x1ffff00000010200(slab|head|node=0|zone=0|
Object 0x0000000000400540 @offset=1344 fp=0x0000000000000000
Redzone  0000000000400500: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
Redzone  0000000000400510: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
Redzone  0000000000400520: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
Redzone  0000000000400530: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
Object   0000000000400540: 00 01 00 03 00 00 00 00 00 00 00 00 00 00 00 00  ................
Object   0000000000400550: f3 86 81 f2 f4 82 f8 82 f0 f0 f0 f0 f0 f0 f0 f2  ................
Object   0000000000400560: 00 00 00 00 80 00 00 00 cc cc cc cc cc cc cc cc  ................
Object   0000000000400570: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
Redzone  0000000000400580: cc cc cc cc cc cc cc cc                          ........
Padding  00000000004005d4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a  ZZZZZZZZZZZZZZZZ
Padding  00000000004005e4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a  ZZZZZZZZZZZZZZZZ
Padding  00000000004005f4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a              ZZZZZZZZZZZZ
CPU: 6 PID: 121030 Comm: 116-pai-crypto. Not tainted 6.3.0-20230221.rc0.git4.99b8246b2d71.300.fc37.s390x+debug #1
Hardware name: IBM 3931 A01 704 (z/VM 7.3.0)
Call Trace:
[&lt;000000032aa034ec&gt;] dump_stack_lvl+0xac/0x100
[&lt;0000000329f5a6cc&gt;] check_bytes_and_report+0x104/0x140
[&lt;0000000329f5aa78&gt;] check_object+0x370/0x3c0
[&lt;0000000329f5ede6&gt;] free_debug_processing+0x15e/0x348
[&lt;0000000329f5f06a&gt;] free_to_partial_list+0x9a/0x2f0
[&lt;0000000329f5f4a4&gt;] __slab_free+0x1e4/0x3a8
[&lt;0000000329f61768&gt;] __kmem_cache_free+0x308/0x358
[&lt;000000032a91465c&gt;] iucv_cpu_dead+0x6c/0x88
[&lt;0000000329c2fc66&gt;] cpuhp_invoke_callback+0x156/0x2f0
[&lt;000000032aa062da&gt;] _cpu_down.constprop.0+0x22a/0x5e0
[&lt;0000000329c3243e&gt;] cpu_device_down+0x4e/0x78
[&lt;000000032a61dee0&gt;] device_offline+0xc8/0x118
[&lt;000000032a61e048&gt;] online_store+0x60/0xe0
[&lt;000000032a08b6b0&gt;] kernfs_fop_write_iter+0x150/0x1e8
[&lt;0000000329fab65c&gt;] vfs_write+0x174/0x360
[&lt;0000000329fab9fc&gt;] ksys_write+0x74/0x100
[&lt;000000032aa03a5a&gt;] __do_syscall+0x1da/0x208
[&lt;000000032aa177b2&gt;] system_call+0x82/0xb0
INFO: lockdep is turned off.
FIX dma-kmalloc-64: Restoring kmalloc Redzone 0x0000000000400564-0x0000000000400567=0xcc
FIX dma-kmalloc-64: Object at 0x0000000000400540 not freed

Fixes: 2356f4cb1911 ("[S390]: Rewrite of the IUCV base code, part 2")
Signed-off-by: Alexandra Winter &lt;wintera@linux.ibm.com&gt;
Link: https://lore.kernel.org/r/20230315131435.4113889-1-wintera@linux.ibm.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: keep sk-&gt;sk_forward_alloc as small as possible</title>
<updated>2022-06-10T23:21:27+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2022-06-09T06:34:11+00:00</published>
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<id>urn:sha1:4890b686f4088c90432149bd6de567e621266fa2</id>
<content type='text'>
Currently, tcp_memory_allocated can hit tcp_mem[] limits quite fast.

Each TCP socket can forward allocate up to 2 MB of memory, even after
flow became less active.

10,000 sockets can have reserved 20 GB of memory,
and we have no shrinker in place to reclaim that.

Instead of trying to reclaim the extra allocations in some places,
just keep sk-&gt;sk_forward_alloc values as small as possible.

This should not impact performance too much now we have per-cpu
reserves: Changes to tcp_memory_allocated should not be too frequent.

For sockets not using SO_RESERVE_MEM:
 - idle sockets (no packets in tx/rx queues) have zero forward alloc.
 - non idle sockets have a forward alloc smaller than one page.

Note:

 - Removal of SK_RECLAIM_CHUNK and SK_RECLAIM_THRESHOLD
   is left to MPTCP maintainers as a follow up.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Acked-by: Soheil Hassas Yeganeh &lt;soheil@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: remove noblock parameter from skb_recv_datagram()</title>
<updated>2022-04-06T12:45:26+00:00</updated>
<author>
<name>Oliver Hartkopp</name>
<email>socketcan@hartkopp.net</email>
</author>
<published>2022-04-04T16:30:22+00:00</published>
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<id>urn:sha1:f4b41f062c424209e3939a81e6da022e049a45f2</id>
<content type='text'>
skb_recv_datagram() has two parameters 'flags' and 'noblock' that are
merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)'

As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags'
into 'flags' and 'noblock' with finally obsolete bit operations like this:

skb_recv_datagram(sk, flags &amp; ~MSG_DONTWAIT, flags &amp; MSG_DONTWAIT, &amp;rc);

And this is not even done consistently with the 'flags' parameter.

This patch removes the obsolete and costly splitting into two parameters
and only performs bit operations when really needed on the caller side.

One missing conversion thankfully reported by kernel test robot. I missed
to enable kunit tests to build the mctp code.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Oliver Hartkopp &lt;socketcan@hartkopp.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>s390/iucv: sort out physical vs virtual pointers usage</title>
<updated>2022-02-23T00:09:13+00:00</updated>
<author>
<name>Alexander Gordeev</name>
<email>agordeev@linux.ibm.com</email>
</author>
<published>2022-02-21T14:56:32+00:00</published>
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<id>urn:sha1:ab847d03a5e41a59a25009d2630682bd55398fab</id>
<content type='text'>
Fix virtual vs physical address confusion (which currently are the same).

Reviewed-by: Alexandra Winter &lt;wintera@linux.ibm.com&gt;
Reviewed-by: Wenjia Zhang &lt;wenjia@linux.ibm.com&gt;
Signed-off-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Signed-off-by: Alexandra Winter &lt;wintera@linux.ibm.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: Don't include filter.h from net/sock.h</title>
<updated>2021-12-29T16:48:14+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2021-12-29T00:49:13+00:00</published>
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<id>urn:sha1:b6459415b384cb829f0b2a4268f211c789f6cf0b</id>
<content type='text'>
sock.h is pretty heavily used (5k objects rebuilt on x86 after
it's touched). We can drop the include of filter.h from it and
add a forward declaration of struct sk_filter instead.
This decreases the number of rebuilt objects when bpf.h
is touched from ~5k to ~1k.

There's a lot of missing includes this was masking. Primarily
in networking tho, this time.

Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Marc Kleine-Budde &lt;mkl@pengutronix.de&gt;
Acked-by: Florian Fainelli &lt;f.fainelli@gmail.com&gt;
Acked-by: Nikolay Aleksandrov &lt;nikolay@nvidia.com&gt;
Acked-by: Stefano Garzarella &lt;sgarzare@redhat.com&gt;
Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org
</content>
</entry>
<entry>
<title>net/af_iucv: Use struct_group() to zero struct iucv_sock region</title>
<updated>2021-11-19T11:52:25+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2021-11-18T20:34:07+00:00</published>
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<id>urn:sha1:b5d8cf0af167f3ab9f4cfe44918cde01e20a1222</id>
<content type='text'>
In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memset(), avoid intentionally writing across
neighboring fields.

Add struct_group() to mark the region of struct iucv_sock that gets
initialized to zero. Avoid the future warning:

In function 'fortify_memset_chk',
    inlined from 'iucv_sock_alloc' at net/iucv/af_iucv.c:476:2:
./include/linux/fortify-string.h:199:4: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning]
  199 |    __write_overflow_field(p_size_field, size);
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Acked-by: Karsten Graul &lt;kgraul@linux.ibm.com&gt;
Link: https://lore.kernel.org/lkml/19ff61a0-0cda-6000-ce56-dc6b367c00d6@linux.ibm.com/
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>net/af_iucv: fix kernel doc comments</title>
<updated>2021-11-19T11:12:30+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>hca@linux.ibm.com</email>
</author>
<published>2021-11-18T16:06:04+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=7c8e1a9155ef7db11672107ee99ad55a0815e3a6'/>
<id>urn:sha1:7c8e1a9155ef7db11672107ee99ad55a0815e3a6</id>
<content type='text'>
Fix kernel doc comments where appropriate, or remove incorrect kernel
doc indicators.

Acked-by: Julian Wiedmann &lt;jwi@linux.ibm.com&gt;
Signed-off-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Karsten Graul &lt;kgraul@linux.ibm.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
</feed>
