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<title>user/sven/linux.git/lib, branch v5.15.76</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.15.76</id>
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<updated>2022-10-26T10:35:55Z</updated>
<entry>
<title>lib/Kconfig.debug: Add check for non-constant .{s,u}leb128 support to DWARF5</title>
<updated>2022-10-26T10:35:55Z</updated>
<author>
<name>Nathan Chancellor</name>
<email>nathan@kernel.org</email>
</author>
<published>2022-10-14T20:42:11Z</published>
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<id>urn:sha1:0e63de6d7e4ca9257fb32c0293bbd95e355d0f2d</id>
<content type='text'>
commit 0a6de78cff600cb991f2a1b7ed376935871796a0 upstream.

When building with a RISC-V kernel with DWARF5 debug info using clang
and the GNU assembler, several instances of the following error appear:

  /tmp/vgettimeofday-48aa35.s:2963: Error: non-constant .uleb128 is not supported

Dumping the .s file reveals these .uleb128 directives come from
.debug_loc and .debug_ranges:

  .Ldebug_loc0:
          .byte   4                               # DW_LLE_offset_pair
          .uleb128 .Lfunc_begin0-.Lfunc_begin0    #   starting offset
          .uleb128 .Ltmp1-.Lfunc_begin0           #   ending offset
          .byte   1                               # Loc expr size
          .byte   90                              # DW_OP_reg10
          .byte   0                               # DW_LLE_end_of_list

  .Ldebug_ranges0:
          .byte   4                               # DW_RLE_offset_pair
          .uleb128 .Ltmp6-.Lfunc_begin0           #   starting offset
          .uleb128 .Ltmp27-.Lfunc_begin0          #   ending offset
          .byte   4                               # DW_RLE_offset_pair
          .uleb128 .Ltmp28-.Lfunc_begin0          #   starting offset
          .uleb128 .Ltmp30-.Lfunc_begin0          #   ending offset
          .byte   0                               # DW_RLE_end_of_list

There is an outstanding binutils issue to support a non-constant operand
to .sleb128 and .uleb128 in GAS for RISC-V but there does not appear to
be any movement on it, due to concerns over how it would work with
linker relaxation.

To avoid these build errors, prevent DWARF5 from being selected when
using clang and an assembler that does not have support for these symbol
deltas, which can be easily checked in Kconfig with as-instr plus the
small test program from the dwz test suite from the binutils issue.

Link: https://sourceware.org/bugzilla/show_bug.cgi?id=27215
Link: https://github.com/ClangBuiltLinux/linux/issues/1719
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
[nathan: Fix conflicts due to lack of f9b3cd24578401e]
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>Kconfig.debug: add toolchain checks for DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT</title>
<updated>2022-10-26T10:35:55Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2022-10-04T16:29:04Z</published>
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<id>urn:sha1:84cd0b20fada657debc0a6bc820648c120588ea6</id>
<content type='text'>
commit bb1435f3f575b5213eaf27434efa3971f51c01de upstream.

CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT does not give explicit
-gdwarf-* flag. The actual DWARF version is up to the toolchain.

The combination of GCC and GAS works fine, and Clang with the integrated
assembler is good too.

The combination of Clang and GAS is tricky, but at least, the -g flag
works for Clang &lt;=13, which defaults to DWARF v4.

Clang 14 switched its default to DWARF v5.

Now, CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT has the same issue as
addressed by commit 98cd6f521f10 ("Kconfig: allow explicit opt in to
DWARF v5").

CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y for Clang &gt;= 14 and
GAS &lt; 2.35 produces a ton of errors like follows:

  /tmp/main-c2741c.s: Assembler messages:
  /tmp/main-c2741c.s:109: Error: junk at end of line, first unrecognized character is `"'
  /tmp/main-c2741c.s:109: Error: file number less than one

Add 'depends on' to check toolchains.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Reviewed-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
[nathan: Fix conflict due to lack of f9b3cd24578401e]
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>Kconfig.debug: simplify the dependency of DEBUG_INFO_DWARF4/5</title>
<updated>2022-10-26T10:35:55Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2022-10-04T16:29:03Z</published>
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<id>urn:sha1:371aaf6b48f5b20708dfc8cc319d66c7cce7f50a</id>
<content type='text'>
commit 4f001a21080ff2e2f0e1c3692f5e119aedbb3bc1 upstream.

Commit c0a5c81ca9be ("Kconfig.debug: drop GCC 5+ version check for
DWARF5") could have cleaned up the code a bit more.

"CC_IS_CLANG &amp;&amp;" is unneeded. No functional change is intended.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Reviewed-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
[nathan: Only apply to DWARF5, as 5.15 does not have 32ef9e5054ec032]
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>dyndbg: drop EXPORTed dynamic_debug_exec_queries</title>
<updated>2022-10-26T10:35:08Z</updated>
<author>
<name>Jim Cromie</name>
<email>jim.cromie@gmail.com</email>
</author>
<published>2022-09-04T21:40:46Z</published>
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<id>urn:sha1:aecb632674b7a5f4260aec8b2dd8089bd885a053</id>
<content type='text'>
[ Upstream commit e26ef3af964acfea311403126acee8c56c89e26b ]

This exported fn is unused, and will not be needed. Lets dump it.

The export was added to let drm control pr_debugs, as part of using
them to avoid drm_debug_enabled overheads.  But its better to just
implement the drm.debug bitmap interface, then its available for
everyone.

Fixes: a2d375eda771 ("dyndbg: refine export, rename to dynamic_debug_exec_queries()")
Fixes: 4c0d77828d4f ("dyndbg: export ddebug_exec_queries")
Acked-by: Jason Baron &lt;jbaron@akamai.com&gt;
Acked-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jim Cromie &lt;jim.cromie@gmail.com&gt;
Link: https://lore.kernel.org/r/20220904214134.408619-10-jim.cromie@gmail.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>dyndbg: let query-modname override actual module name</title>
<updated>2022-10-26T10:35:08Z</updated>
<author>
<name>Jim Cromie</name>
<email>jim.cromie@gmail.com</email>
</author>
<published>2022-09-04T21:40:44Z</published>
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<content type='text'>
[ Upstream commit e75ef56f74965f426dd819a41336b640ffdd8fbc ]

dyndbg's control-parser: ddebug_parse_query(), requires that search
terms: module, func, file, lineno, are used only once in a query; a
thing cannot be named both foo and bar.

The cited commit added an overriding module modname, taken from the
module loader, which is authoritative.  So it set query.module 1st,
which disallowed its use in the query-string.

But now, its useful to allow a module-load to enable classes across a
whole (or part of) a subsystem at once.

  # enable (dynamic-debug in) drm only
  modprobe drm dyndbg="class DRM_UT_CORE +p"

  # get drm_helper too
  modprobe drm dyndbg="class DRM_UT_CORE module drm* +p"

  # get everything that knows DRM_UT_CORE
  modprobe drm dyndbg="class DRM_UT_CORE module * +p"

  # also for boot-args:
  drm.dyndbg="class DRM_UT_CORE module * +p"

So convert the override into a default, by filling it only when/after
the query-string omitted the module.

NB: the query class FOO handling is forthcoming.

Fixes: 8e59b5cfb9a6 dynamic_debug: add modname arg to exec_query callchain
Acked-by: Jason Baron &lt;jbaron@akamai.com&gt;
Acked-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jim Cromie &lt;jim.cromie@gmail.com&gt;
Link: https://lore.kernel.org/r/20220904214134.408619-8-jim.cromie@gmail.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>dyndbg: fix static_branch manipulation</title>
<updated>2022-10-26T10:35:08Z</updated>
<author>
<name>Jim Cromie</name>
<email>jim.cromie@gmail.com</email>
</author>
<published>2022-09-04T21:40:38Z</published>
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<id>urn:sha1:49d85932f7d2e8d2b4dc06cf878c18a73dd72e35</id>
<content type='text'>
[ Upstream commit ee879be38bc87f8cedc79ae2742958db6533ca59 ]

In https://lore.kernel.org/lkml/20211209150910.GA23668@axis.com/

Vincent's patch commented on, and worked around, a bug toggling
static_branch's, when a 2nd PRINTK-ish flag was added.  The bug
results in a premature static_branch_disable when the 1st of 2 flags
was disabled.

The cited commit computed newflags, but then in the JUMP_LABEL block,
failed to use that result, instead using just one of the terms in it.
Using newflags instead made the code work properly.

This is Vincents test-case, reduced.  It needs the 2nd flag to
demonstrate the bug, but it's explanatory here.

pt_test() {
    echo 5 &gt; /sys/module/dynamic_debug/verbose

    site="module tcp" # just one callsite
    echo " $site =_ " &gt; /proc/dynamic_debug/control # clear it

    # A B ~A ~B
    for flg in +T +p "-T #broke here" -p; do
	echo " $site $flg " &gt; /proc/dynamic_debug/control
    done;

    # A B ~B ~A
    for flg in +T +p "-p #broke here" -T; do
	echo " $site $flg " &gt; /proc/dynamic_debug/control
    done
}
pt_test

Fixes: 84da83a6ffc0 dyndbg: combine flags &amp; mask into a struct, simplify with it
CC: vincent.whitchurch@axis.com
Acked-by: Jason Baron &lt;jbaron@akamai.com&gt;
Acked-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Jim Cromie &lt;jim.cromie@gmail.com&gt;
Link: https://lore.kernel.org/r/20220904214134.408619-2-jim.cromie@gmail.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>once: add DO_ONCE_SLOW() for sleepable contexts</title>
<updated>2022-10-26T10:34:49Z</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2022-10-01T20:51:02Z</published>
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<id>urn:sha1:7aef5082c56e49c785271649d1f486544d33ef61</id>
<content type='text'>
[ Upstream commit 62c07983bef9d3e78e71189441e1a470f0d1e653 ]

Christophe Leroy reported a ~80ms latency spike
happening at first TCP connect() time.

This is because __inet_hash_connect() uses get_random_once()
to populate a perturbation table which became quite big
after commit 4c2c8f03a5ab ("tcp: increase source port perturb table to 2^16")

get_random_once() uses DO_ONCE(), which block hard irqs for the duration
of the operation.

This patch adds DO_ONCE_SLOW() which uses a mutex instead of a spinlock
for operations where we prefer to stay in process context.

Then __inet_hash_connect() can use get_random_slow_once()
to populate its perturbation table.

Fixes: 4c2c8f03a5ab ("tcp: increase source port perturb table to 2^16")
Fixes: 190cc82489f4 ("tcp: change source port randomizarion at connect() time")
Reported-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Link: https://lore.kernel.org/netdev/CANn89iLAEYBaoYajy0Y9UmGFff5GPxDUoG-ErVB2jDdRNQ5Tug@mail.gmail.com/T/#t
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Willy Tarreau &lt;w@1wt.eu&gt;
Tested-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>crypto: lib - remove unneeded selection of XOR_BLOCKS</title>
<updated>2022-09-05T08:30:03Z</updated>
<author>
<name>Eric Biggers</name>
<email>ebiggers@google.com</email>
</author>
<published>2022-08-26T05:04:56Z</published>
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<content type='text'>
commit 874b301985ef2f89b8b592ad255e03fb6fbfe605 upstream.

CRYPTO_LIB_CHACHA_GENERIC doesn't need to select XOR_BLOCKS.  It perhaps
was thought that it's needed for __crypto_xor, but that's not the case.

Enabling XOR_BLOCKS is problematic because the XOR_BLOCKS code runs a
benchmark when it is initialized.  That causes a boot time regression on
systems that didn't have it enabled before.

Therefore, remove this unnecessary and problematic selection.

Fixes: e56e18985596 ("lib/crypto: add prompts back to crypto libraries")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ratelimit: Fix data-races in ___ratelimit().</title>
<updated>2022-08-31T15:16:43Z</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-08-23T17:46:48Z</published>
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<id>urn:sha1:0db9ce822f13634e8042405684870da75747005f</id>
<content type='text'>
[ Upstream commit 6bae8ceb90ba76cdba39496db936164fa672b9be ]

While reading rs-&gt;interval and rs-&gt;burst, they can be changed
concurrently via sysctl (e.g. net_ratelimit_state).  Thus, we
need to add READ_ONCE() to their readers.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>lib/list_debug.c: Detect uninitialized lists</title>
<updated>2022-08-25T09:40:40Z</updated>
<author>
<name>Guenter Roeck</name>
<email>linux@roeck-us.net</email>
</author>
<published>2022-05-31T22:29:51Z</published>
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<id>urn:sha1:ce0432aa8944496edcecd0ce6008146190e45980</id>
<content type='text'>
[ Upstream commit 0cc011c576aaa4de505046f7a6c90933d7c749a9 ]

In some circumstances, attempts are made to add entries to or to remove
entries from an uninitialized list.  A prime example is
amdgpu_bo_vm_destroy(): It is indirectly called from
ttm_bo_init_reserved() if that function fails, and tries to remove an
entry from a list.  However, that list is only initialized in
amdgpu_bo_create_vm() after the call to ttm_bo_init_reserved() returned
success.  This results in crashes such as

 BUG: kernel NULL pointer dereference, address: 0000000000000000
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: 0000 [#1] PREEMPT SMP NOPTI
 CPU: 1 PID: 1479 Comm: chrome Not tainted 5.10.110-15768-g29a72e65dae5
 Hardware name: Google Grunt/Grunt, BIOS Google_Grunt.11031.149.0 07/15/2020
 RIP: 0010:__list_del_entry_valid+0x26/0x7d
 ...
 Call Trace:
  amdgpu_bo_vm_destroy+0x48/0x8b
  ttm_bo_init_reserved+0x1d7/0x1e0
  amdgpu_bo_create+0x212/0x476
  ? amdgpu_bo_user_destroy+0x23/0x23
  ? kmem_cache_alloc+0x60/0x271
  amdgpu_bo_create_vm+0x40/0x7d
  amdgpu_vm_pt_create+0xe8/0x24b
 ...

Check if the list's prev and next pointers are NULL to catch such problems.

Link: https://lkml.kernel.org/r/20220531222951.92073-1-linux@roeck-us.net
Signed-off-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
