<feed xmlns='http://www.w3.org/2005/Atom'>
<title>lwn.git/arch/sparc/kernel/ds.c, branch docs-5.13</title>
<subtitle>Linux kernel documentation tree maintained by Jonathan Corbet</subtitle>
<id>http://mirrors.hust.edu.cn/git/lwn.git/atom?h=docs-5.13</id>
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<updated>2020-05-08T01:49:04+00:00</updated>
<entry>
<title>sparc64: Replace zero-length array with flexible-array</title>
<updated>2020-05-08T01:49:04+00:00</updated>
<author>
<name>Gustavo A. R. Silva</name>
<email>gustavoars@kernel.org</email>
</author>
<published>2020-05-07T19:23:02+00:00</published>
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<id>urn:sha1:60da7d0bc7482a30817c73fdc8152123d19919f8</id>
<content type='text'>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>sparc: Replace cpu_up/down() with add/remove_cpu()</title>
<updated>2020-03-25T11:59:36+00:00</updated>
<author>
<name>Qais Yousef</name>
<email>qais.yousef@arm.com</email>
</author>
<published>2020-03-23T13:51:04+00:00</published>
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<id>urn:sha1:7f6707a2040fecfae131752b5097c028885cc161</id>
<content type='text'>
The core device API performs extra housekeeping bits that are missing
from directly calling cpu_up/down().

See commit a6717c01ddc2 ("powerpc/rtas: use device model APIs and
serialization during LPM") for an example description of what might go
wrong.

This also prepares to make cpu_up/down() a private interface of the CPU
subsystem.

Signed-off-by: Qais Yousef &lt;qais.yousef@arm.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Link: https://lkml.kernel.org/r/20200323135110.30522-12-qais.yousef@arm.com

</content>
</entry>
<entry>
<title>treewide: Add SPDX license identifier for more missed files</title>
<updated>2019-05-21T08:50:45+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2019-05-19T12:08:20+00:00</published>
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<id>urn:sha1:09c434b8a0047c69e48499de0107de312901e798</id>
<content type='text'>
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively</title>
<updated>2019-04-09T12:19:06+00:00</updated>
<author>
<name>Sakari Ailus</name>
<email>sakari.ailus@linux.intel.com</email>
</author>
<published>2019-03-25T19:32:28+00:00</published>
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<id>urn:sha1:d75f773c86a2b8b7278e2c33343b46a4024bc002</id>
<content type='text'>
%pF and %pf are functionally equivalent to %pS and %ps conversion
specifiers. The former are deprecated, therefore switch the current users
to use the preferred variant.

The changes have been produced by the following command:

	git grep -l '%p[fF]' | grep -v '^\(tools\|Documentation\)/' | \
	while read i; do perl -i -pe 's/%pf/%ps/g; s/%pF/%pS/g;' $i; done

And verifying the result.

Link: http://lkml.kernel.org/r/20190325193229.23390-1-sakari.ailus@linux.intel.com
Cc: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Cc: linux-arm-kernel@lists.infradead.org
Cc: sparclinux@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: xen-devel@lists.xenproject.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
Cc: linux-nvdimm@lists.01.org
Cc: linux-pci@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: linux-btrfs@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: linux-mm@kvack.org
Cc: ceph-devel@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Sakari Ailus &lt;sakari.ailus@linux.intel.com&gt;
Acked-by: David Sterba &lt;dsterba@suse.com&gt; (for btrfs)
Acked-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt; (for mm/memblock.c)
Acked-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt; (for drivers/pci)
Acked-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Petr Mladek &lt;pmladek@suse.com&gt;
</content>
</entry>
<entry>
<title>sparc64: Fix build warnings with gcc 7.</title>
<updated>2017-06-01T16:42:46+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2017-06-01T16:42:46+00:00</published>
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<id>urn:sha1:0fde7ad71ee371ede73b3f326e58f9e8d102feb6</id>
<content type='text'>
arch/sparc/kernel/ds.c: In function ‘register_services’:
arch/sparc/kernel/ds.c:912:3: error: ‘strcpy’: writing at least 1 byte
into a region of size 0 overflows the destination

Reported-by: Anatoly Pugachev &lt;matorola@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>sched/headers: Prepare for new header dependencies before moving code to &lt;linux/sched/clock.h&gt;</title>
<updated>2017-03-02T07:42:27+00:00</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@kernel.org</email>
</author>
<published>2017-02-01T15:36:40+00:00</published>
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<id>urn:sha1:e601757102cfd3eeae068f53b3bc1234f3a2b2e9</id>
<content type='text'>
We are going to split &lt;linux/sched/clock.h&gt; out of &lt;linux/sched.h&gt;, which
will have to be picked up from other headers and .c files.

Create a trivial placeholder &lt;linux/sched/clock.h&gt; file that just
maps to &lt;linux/sched.h&gt; to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Mike Galbraith &lt;efault@gmx.de&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>sparc64: Move request_irq() from ldc_bind() to ldc_alloc()</title>
<updated>2014-09-17T01:31:31+00:00</updated>
<author>
<name>Sowmini Varadhan</name>
<email>sowmini.varadhan@oracle.com</email>
</author>
<published>2014-09-16T15:37:08+00:00</published>
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<id>urn:sha1:c21c4ab0d6921f7160a43216fa6973b5924de561</id>
<content type='text'>
The request_irq() needs to be done from ldc_alloc()
to avoid the following (caught by lockdep)

 [00000000004a0738] __might_sleep+0xf8/0x120
 [000000000058bea4] kmem_cache_alloc_trace+0x184/0x2c0
 [00000000004faf80] request_threaded_irq+0x80/0x160
 [000000000044f71c] ldc_bind+0x7c/0x220
 [0000000000452454] vio_port_up+0x54/0xe0
 [00000000101f6778] probe_disk+0x38/0x220 [sunvdc]
 [00000000101f6b8c] vdc_port_probe+0x22c/0x300 [sunvdc]
 [0000000000451a88] vio_device_probe+0x48/0x60
 [000000000074c56c] really_probe+0x6c/0x300
 [000000000074c83c] driver_probe_device+0x3c/0xa0
 [000000000074c92c] __driver_attach+0x8c/0xa0
 [000000000074a6ec] bus_for_each_dev+0x6c/0xa0
 [000000000074c1dc] driver_attach+0x1c/0x40
 [000000000074b0fc] bus_add_driver+0xbc/0x280

Signed-off-by: Sowmini Varadhan &lt;sowmini.varadhan@oracle.com&gt;
Acked-by: Dwight Engen &lt;dwight.engen@oracle.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>sparc: fix ldom_reboot buffer overflow harder</title>
<updated>2013-10-03T00:01:56+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2013-10-02T05:13:34+00:00</published>
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<id>urn:sha1:20928bd3f08afb036c096d9559d581926b895918</id>
<content type='text'>
The length argument to strlcpy was still wrong. It could overflow the end of
full_boot_str by 5 bytes. Instead of strcat and strlcpy, just use snprint.

Reported-by: Brad Spengler &lt;spender@grsecurity.net&gt;
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>sparc64: Fix buggy strlcpy() conversion in ldom_reboot().</title>
<updated>2013-09-27T20:46:04+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2013-09-27T20:46:04+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=2bd161a605f1f84a5fc8a4fe8410113a94f79355'/>
<id>urn:sha1:2bd161a605f1f84a5fc8a4fe8410113a94f79355</id>
<content type='text'>
Commit 117a0c5fc9c2d06045bd217385b2b39ea426b5a6 ("sparc: kernel: using
strlcpy() instead of strcpy()") added a bug to ldom_reboot in
arch/sparc/kernel/ds.c

-		strcpy(full_boot_str + strlen("boot "), boot_command);
+				     strlcpy(full_boot_str + strlen("boot "), boot_command,
+				     			     sizeof(full_boot_str + strlen("boot ")));

That last sizeof() expression evaluates to sizeof(size_t) which is
not what was intended.

Also even the corrected:

     sizeof(full_boot_str) + strlen("boot ")

is not right as the destination buffer length is just plain
"sizeof(full_boot_str)" and that's what the final argument
should be.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>sparc: delete __cpuinit/__CPUINIT usage from all users</title>
<updated>2013-07-14T23:36:52+00:00</updated>
<author>
<name>Paul Gortmaker</name>
<email>paul.gortmaker@windriver.com</email>
</author>
<published>2013-06-17T19:43:14+00:00</published>
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<id>urn:sha1:2066aadd53c563445039d6490b685783816270ec</id>
<content type='text'>
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit  -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings.  In any case, they are temporary and harmless.

This removes all the arch/sparc uses of the __cpuinit macros from
C files and removes __CPUINIT from assembly files.  Note that even
though arch/sparc/kernel/trampoline_64.S has instances of ".previous"
in it, they are all paired off against explicit ".section" directives,
and not implicitly paired with __CPUINIT (unlike mips and arm were).

[1] https://lkml.org/lkml/2013/5/20/589

Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: sparclinux@vger.kernel.org
Signed-off-by: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
</content>
</entry>
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