<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/scripts, branch linux-4.19.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>modpost: remove incorrect code in do_eisa_entry()</title>
<updated>2024-12-05T09:59:42+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2024-11-19T23:56:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=94a6159f610cd97cccc8735e4ddc094f16438a18'/>
<id>94a6159f610cd97cccc8735e4ddc094f16438a18</id>
<content type='text'>
[ Upstream commit 0c3e091319e4748cb36ac9a50848903dc6f54054 ]

This function contains multiple bugs after the following commits:

 - ac551828993e ("modpost: i2c aliases need no trailing wildcard")
 - 6543becf26ff ("mod/file2alias: make modalias generation safe for cross compiling")

Commit ac551828993e inserted the following code to do_eisa_entry():

    else
            strcat(alias, "*");

This is incorrect because 'alias' is uninitialized. If it is not
NULL-terminated, strcat() could cause a buffer overrun.

Even if 'alias' happens to be zero-filled, it would output:

    MODULE_ALIAS("*");

This would match anything. As a result, the module could be loaded by
any unrelated uevent from an unrelated subsystem.

Commit ac551828993e introduced another bug.            

Prior to that commit, the conditional check was:

    if (eisa-&gt;sig[0])

This checked if the first character of eisa_device_id::sig was not '\0'.

However, commit ac551828993e changed it as follows:

    if (sig[0])

sig[0] is NOT the first character of the eisa_device_id::sig. The
type of 'sig' is 'char (*)[8]', meaning that the type of 'sig[0]' is
'char [8]' instead of 'char'. 'sig[0]' and 'symval' refer to the same
address, which never becomes NULL.

The correct conversion would have been:

    if ((*sig)[0])

However, this if-conditional was meaningless because the earlier change
in commit ac551828993e was incorrect.

This commit removes the entire incorrect code, which should never have
been executed.

Fixes: ac551828993e ("modpost: i2c aliases need no trailing wildcard")
Fixes: 6543becf26ff ("mod/file2alias: make modalias generation safe for cross compiling")
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0c3e091319e4748cb36ac9a50848903dc6f54054 ]

This function contains multiple bugs after the following commits:

 - ac551828993e ("modpost: i2c aliases need no trailing wildcard")
 - 6543becf26ff ("mod/file2alias: make modalias generation safe for cross compiling")

Commit ac551828993e inserted the following code to do_eisa_entry():

    else
            strcat(alias, "*");

This is incorrect because 'alias' is uninitialized. If it is not
NULL-terminated, strcat() could cause a buffer overrun.

Even if 'alias' happens to be zero-filled, it would output:

    MODULE_ALIAS("*");

This would match anything. As a result, the module could be loaded by
any unrelated uevent from an unrelated subsystem.

Commit ac551828993e introduced another bug.            

Prior to that commit, the conditional check was:

    if (eisa-&gt;sig[0])

This checked if the first character of eisa_device_id::sig was not '\0'.

However, commit ac551828993e changed it as follows:

    if (sig[0])

sig[0] is NOT the first character of the eisa_device_id::sig. The
type of 'sig' is 'char (*)[8]', meaning that the type of 'sig[0]' is
'char [8]' instead of 'char'. 'sig[0]' and 'symval' refer to the same
address, which never becomes NULL.

The correct conversion would have been:

    if ((*sig)[0])

However, this if-conditional was meaningless because the earlier change
in commit ac551828993e was incorrect.

This commit removes the entire incorrect code, which should never have
been executed.

Fixes: ac551828993e ("modpost: i2c aliases need no trailing wildcard")
Fixes: 6543becf26ff ("mod/file2alias: make modalias generation safe for cross compiling")
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kbuild: Use uname for LINUX_COMPILE_HOST detection</title>
<updated>2024-12-05T09:59:29+00:00</updated>
<author>
<name>Chris Down</name>
<email>chris@chrisdown.name</email>
</author>
<published>2020-10-20T09:34:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fef0b00f318f4017f51c008bc99cd2d524a407ec'/>
<id>fef0b00f318f4017f51c008bc99cd2d524a407ec</id>
<content type='text'>
commit 1e66d50ad3a1dbf0169b14d502be59a4b1213149 upstream.

`hostname` may not be present on some systems as it's not mandated by
POSIX/SUSv4. This isn't just a theoretical problem: on Arch Linux,
`hostname` is provided by `inetutils`, which isn't part of the base
distribution.

    ./scripts/mkcompile_h: line 38: hostname: command not found

Use `uname -n` instead, which is more likely to be available (and
mandated by standards).

Signed-off-by: Chris Down &lt;chris@chrisdown.name&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 1e66d50ad3a1dbf0169b14d502be59a4b1213149 upstream.

`hostname` may not be present on some systems as it's not mandated by
POSIX/SUSv4. This isn't just a theoretical problem: on Arch Linux,
`hostname` is provided by `inetutils`, which isn't part of the base
distribution.

    ./scripts/mkcompile_h: line 38: hostname: command not found

Use `uname -n` instead, which is more likely to be available (and
mandated by standards).

Signed-off-by: Chris Down &lt;chris@chrisdown.name&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>scripts: kconfig: merge_config: config files: add a trailing newline</title>
<updated>2024-11-08T15:19:02+00:00</updated>
<author>
<name>Anders Roxell</name>
<email>anders.roxell@linaro.org</email>
</author>
<published>2024-08-05T09:22:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6a130ec2f0646a8544308b6cf983269d5a2a7fa0'/>
<id>6a130ec2f0646a8544308b6cf983269d5a2a7fa0</id>
<content type='text'>
[ Upstream commit 33330bcf031818e60a816db0cfd3add9eecc3b28 ]

When merging files without trailing newlines at the end of the file, two
config fragments end up at the same row if file1.config doens't have a
trailing newline at the end of the file.

file1.config "CONFIG_1=y"
file2.config "CONFIG_2=y"
./scripts/kconfig/merge_config.sh -m .config file1.config file2.config

This will generate a .config looking like this.
cat .config
...
CONFIG_1=yCONFIG_2=y"

Making sure so we add a newline at the end of every config file that is
passed into the script.

Signed-off-by: Anders Roxell &lt;anders.roxell@linaro.org&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 33330bcf031818e60a816db0cfd3add9eecc3b28 ]

When merging files without trailing newlines at the end of the file, two
config fragments end up at the same row if file1.config doens't have a
trailing newline at the end of the file.

file1.config "CONFIG_1=y"
file2.config "CONFIG_2=y"
./scripts/kconfig/merge_config.sh -m .config file1.config file2.config

This will generate a .config looking like this.
cat .config
...
CONFIG_1=yCONFIG_2=y"

Making sure so we add a newline at the end of every config file that is
passed into the script.

Signed-off-by: Anders Roxell &lt;anders.roxell@linaro.org&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kbuild: Fix '-S -c' in x86 stack protector scripts</title>
<updated>2024-08-19T03:32:17+00:00</updated>
<author>
<name>Nathan Chancellor</name>
<email>nathan@kernel.org</email>
</author>
<published>2024-07-26T18:05:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9dd6e5296c8ad1bbb88933b8150383bc0eba9488'/>
<id>9dd6e5296c8ad1bbb88933b8150383bc0eba9488</id>
<content type='text'>
commit 3415b10a03945b0da4a635e146750dfe5ce0f448 upstream.

After a recent change in clang to stop consuming all instances of '-S'
and '-c' [1], the stack protector scripts break due to the kernel's use
of -Werror=unused-command-line-argument to catch cases where flags are
not being properly consumed by the compiler driver:

  $ echo | clang -o - -x c - -S -c -Werror=unused-command-line-argument
  clang: error: argument unused during compilation: '-c' [-Werror,-Wunused-command-line-argument]

This results in CONFIG_STACKPROTECTOR getting disabled because
CONFIG_CC_HAS_SANE_STACKPROTECTOR is no longer set.

'-c' and '-S' both instruct the compiler to stop at different stages of
the pipeline ('-S' after compiling, '-c' after assembling), so having
them present together in the same command makes little sense. In this
case, the test wants to stop before assembling because it is looking at
the textual assembly output of the compiler for either '%fs' or '%gs',
so remove '-c' from the list of arguments to resolve the error.

All versions of GCC continue to work after this change, along with
versions of clang that do or do not contain the change mentioned above.

Cc: stable@vger.kernel.org
Fixes: 4f7fd4d7a791 ("[PATCH] Add the -fstack-protector option to the CFLAGS")
Fixes: 60a5317ff0f4 ("x86: implement x86_32 stack protector")
Link: https://github.com/llvm/llvm-project/commit/6461e537815f7fa68cef06842505353cf5600e9c [1]
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
[nathan: Fixed conflict in 32-bit version due to lack of 3fb0fdb3bbe7]
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 3415b10a03945b0da4a635e146750dfe5ce0f448 upstream.

After a recent change in clang to stop consuming all instances of '-S'
and '-c' [1], the stack protector scripts break due to the kernel's use
of -Werror=unused-command-line-argument to catch cases where flags are
not being properly consumed by the compiler driver:

  $ echo | clang -o - -x c - -S -c -Werror=unused-command-line-argument
  clang: error: argument unused during compilation: '-c' [-Werror,-Wunused-command-line-argument]

This results in CONFIG_STACKPROTECTOR getting disabled because
CONFIG_CC_HAS_SANE_STACKPROTECTOR is no longer set.

'-c' and '-S' both instruct the compiler to stop at different stages of
the pipeline ('-S' after compiling, '-c' after assembling), so having
them present together in the same command makes little sense. In this
case, the test wants to stop before assembling because it is looking at
the textual assembly output of the compiler for either '%fs' or '%gs',
so remove '-c' from the list of arguments to resolve the error.

All versions of GCC continue to work after this change, along with
versions of clang that do or do not contain the change mentioned above.

Cc: stable@vger.kernel.org
Fixes: 4f7fd4d7a791 ("[PATCH] Add the -fstack-protector option to the CFLAGS")
Fixes: 60a5317ff0f4 ("x86: implement x86_32 stack protector")
Link: https://github.com/llvm/llvm-project/commit/6461e537815f7fa68cef06842505353cf5600e9c [1]
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
[nathan: Fixed conflict in 32-bit version due to lack of 3fb0fdb3bbe7]
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kconfig: remove wrong expr_trans_bool()</title>
<updated>2024-07-27T08:33:41+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2024-06-03T16:19:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b366d89859fe7b58894b3698844b551fe32f892a'/>
<id>b366d89859fe7b58894b3698844b551fe32f892a</id>
<content type='text'>
[ Upstream commit 77a92660d8fe8d29503fae768d9f5eb529c88b36 ]

expr_trans_bool() performs an incorrect transformation.

[Test Code]

    config MODULES
            def_bool y
            modules

    config A
            def_bool y
            select C if B != n

    config B
            def_tristate m

    config C
            tristate

[Result]

    CONFIG_MODULES=y
    CONFIG_A=y
    CONFIG_B=m
    CONFIG_C=m

This output is incorrect because CONFIG_C=y is expected.

Documentation/kbuild/kconfig-language.rst clearly explains the function
of the '!=' operator:

    If the values of both symbols are equal, it returns 'n',
    otherwise 'y'.

Therefore, the statement:

    select C if B != n

should be equivalent to:

    select C if y

Or, more simply:

    select C

Hence, the symbol C should be selected by the value of A, which is 'y'.

However, expr_trans_bool() wrongly transforms it to:

    select C if B

Therefore, the symbol C is selected by (A &amp;&amp; B), which is 'm'.

The comment block of expr_trans_bool() correctly explains its intention:

  * bool FOO!=n =&gt; FOO
    ^^^^

If FOO is bool, FOO!=n can be simplified into FOO. This is correct.

However, the actual code performs this transformation when FOO is
tristate:

    if (e-&gt;left.sym-&gt;type == S_TRISTATE) {
                             ^^^^^^^^^^

While it can be fixed to S_BOOLEAN, there is no point in doing so
because expr_tranform() already transforms FOO!=n to FOO when FOO is
bool. (see the "case E_UNEQUAL" part)

expr_trans_bool() is wrong and unnecessary.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 77a92660d8fe8d29503fae768d9f5eb529c88b36 ]

expr_trans_bool() performs an incorrect transformation.

[Test Code]

    config MODULES
            def_bool y
            modules

    config A
            def_bool y
            select C if B != n

    config B
            def_tristate m

    config C
            tristate

[Result]

    CONFIG_MODULES=y
    CONFIG_A=y
    CONFIG_B=m
    CONFIG_C=m

This output is incorrect because CONFIG_C=y is expected.

Documentation/kbuild/kconfig-language.rst clearly explains the function
of the '!=' operator:

    If the values of both symbols are equal, it returns 'n',
    otherwise 'y'.

Therefore, the statement:

    select C if B != n

should be equivalent to:

    select C if y

Or, more simply:

    select C

Hence, the symbol C should be selected by the value of A, which is 'y'.

However, expr_trans_bool() wrongly transforms it to:

    select C if B

Therefore, the symbol C is selected by (A &amp;&amp; B), which is 'm'.

The comment block of expr_trans_bool() correctly explains its intention:

  * bool FOO!=n =&gt; FOO
    ^^^^

If FOO is bool, FOO!=n can be simplified into FOO. This is correct.

However, the actual code performs this transformation when FOO is
tristate:

    if (e-&gt;left.sym-&gt;type == S_TRISTATE) {
                             ^^^^^^^^^^

While it can be fixed to S_BOOLEAN, there is no point in doing so
because expr_tranform() already transforms FOO!=n to FOO when FOO is
bool. (see the "case E_UNEQUAL" part)

expr_trans_bool() is wrong and unnecessary.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kconfig: gconf: give a proper initial state to the Save button</title>
<updated>2024-07-27T08:33:41+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2024-06-01T18:20:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b6d6a91b584a022424d99264741bdfa6b336c83b'/>
<id>b6d6a91b584a022424d99264741bdfa6b336c83b</id>
<content type='text'>
[ Upstream commit 46edf4372e336ef3a61c3126e49518099d2e2e6d ]

Currently, the initial state of the "Save" button is always active.

If none of the CONFIG options are changed while loading the .config
file, the "Save" button should be greyed out.

This can be fixed by calling conf_read() after widget initialization.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 46edf4372e336ef3a61c3126e49518099d2e2e6d ]

Currently, the initial state of the "Save" button is always active.

If none of the CONFIG options are changed while loading the .config
file, the "Save" button should be greyed out.

This can be fixed by calling conf_read() after widget initialization.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>gcc-plugins: Rename last_stmt() for GCC 14+</title>
<updated>2024-07-27T08:33:40+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2023-08-07T16:41:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2d05669ce1f18c1bc51476980a0e8bd107682546'/>
<id>2d05669ce1f18c1bc51476980a0e8bd107682546</id>
<content type='text'>
commit 2e3f65ccfe6b0778b261ad69c9603ae85f210334 upstream.

In GCC 14, last_stmt() was renamed to last_nondebug_stmt(). Add a helper
macro to handle the renaming.

Cc: linux-hardening@vger.kernel.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Thomas Meyer &lt;thomas@m3y3r.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 2e3f65ccfe6b0778b261ad69c9603ae85f210334 upstream.

In GCC 14, last_stmt() was renamed to last_nondebug_stmt(). Add a helper
macro to handle the renaming.

Cc: linux-hardening@vger.kernel.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Thomas Meyer &lt;thomas@m3y3r.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kconfig: fix comparison to constant symbols, 'm', 'n'</title>
<updated>2024-06-16T11:23:37+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2024-05-19T09:22:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6bfda3ef7f6a2c1de30e70d67e901aa966f40c17'/>
<id>6bfda3ef7f6a2c1de30e70d67e901aa966f40c17</id>
<content type='text'>
[ Upstream commit aabdc960a283ba78086b0bf66ee74326f49e218e ]

Currently, comparisons to 'm' or 'n' result in incorrect output.

[Test Code]

    config MODULES
            def_bool y
            modules

    config A
            def_tristate m

    config B
            def_bool A &gt; n

CONFIG_B is unset, while CONFIG_B=y is expected.

The reason for the issue is because Kconfig compares the tristate values
as strings.

Currently, the .type fields in the constant symbol definitions,
symbol_{yes,mod,no} are unspecified, i.e., S_UNKNOWN.

When expr_calc_value() evaluates 'A &gt; n', it checks the types of 'A' and
'n' to determine how to compare them.

The left-hand side, 'A', is a tristate symbol with a value of 'm', which
corresponds to a numeric value of 1. (Internally, 'y', 'm', and 'n' are
represented as 2, 1, and 0, respectively.)

The right-hand side, 'n', has an unknown type, so it is treated as the
string "n" during the comparison.

expr_calc_value() compares two values numerically only when both can
have numeric values. Otherwise, they are compared as strings.

    symbol    numeric value    ASCII code
    -------------------------------------
      y           2             0x79
      m           1             0x6d
      n           0             0x6e

'm' is greater than 'n' if compared numerically (since 1 is greater
than 0), but smaller than 'n' if compared as strings (since the ASCII
code 0x6d is smaller than 0x6e).

Specifying .type=S_TRISTATE for symbol_{yes,mod,no} fixes the above
test code.

Doing so, however, would cause a regression to the following test code.

[Test Code 2]

    config MODULES
            def_bool n
            modules

    config A
            def_tristate n

    config B
            def_bool A = m

You would get CONFIG_B=y, while CONFIG_B should not be set.

The reason is because sym_get_string_value() turns 'm' into 'n' when the
module feature is disabled. Consequently, expr_calc_value() evaluates
'A = n' instead of 'A = m'. This oddity has been hidden because the type
of 'm' was previously S_UNKNOWN instead of S_TRISTATE.

sym_get_string_value() should not tweak the string because the tristate
value has already been correctly calculated. There is no reason to
return the string "n" where its tristate value is mod.

Fixes: 31847b67bec0 ("kconfig: allow use of relations other than (in)equality")
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit aabdc960a283ba78086b0bf66ee74326f49e218e ]

Currently, comparisons to 'm' or 'n' result in incorrect output.

[Test Code]

    config MODULES
            def_bool y
            modules

    config A
            def_tristate m

    config B
            def_bool A &gt; n

CONFIG_B is unset, while CONFIG_B=y is expected.

The reason for the issue is because Kconfig compares the tristate values
as strings.

Currently, the .type fields in the constant symbol definitions,
symbol_{yes,mod,no} are unspecified, i.e., S_UNKNOWN.

When expr_calc_value() evaluates 'A &gt; n', it checks the types of 'A' and
'n' to determine how to compare them.

The left-hand side, 'A', is a tristate symbol with a value of 'm', which
corresponds to a numeric value of 1. (Internally, 'y', 'm', and 'n' are
represented as 2, 1, and 0, respectively.)

The right-hand side, 'n', has an unknown type, so it is treated as the
string "n" during the comparison.

expr_calc_value() compares two values numerically only when both can
have numeric values. Otherwise, they are compared as strings.

    symbol    numeric value    ASCII code
    -------------------------------------
      y           2             0x79
      m           1             0x6d
      n           0             0x6e

'm' is greater than 'n' if compared numerically (since 1 is greater
than 0), but smaller than 'n' if compared as strings (since the ASCII
code 0x6d is smaller than 0x6e).

Specifying .type=S_TRISTATE for symbol_{yes,mod,no} fixes the above
test code.

Doing so, however, would cause a regression to the following test code.

[Test Code 2]

    config MODULES
            def_bool n
            modules

    config A
            def_tristate n

    config B
            def_bool A = m

You would get CONFIG_B=y, while CONFIG_B should not be set.

The reason is because sym_get_string_value() turns 'm' into 'n' when the
module feature is disabled. Consequently, expr_calc_value() evaluates
'A = n' instead of 'A = m'. This oddity has been hidden because the type
of 'm' was previously S_UNKNOWN instead of S_TRISTATE.

sym_get_string_value() should not tweak the string because the tristate
value has already been correctly calculated. There is no reason to
return the string "n" where its tristate value is mod.

Fixes: 31847b67bec0 ("kconfig: allow use of relations other than (in)equality")
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kbuild: Move -Wenum-{compare-conditional,enum-conversion} into W=1</title>
<updated>2024-04-13T10:50:06+00:00</updated>
<author>
<name>Nathan Chancellor</name>
<email>nathan@kernel.org</email>
</author>
<published>2024-03-05T22:12:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=39460da0515e5ef2afc67a184395daf8f97f74a1'/>
<id>39460da0515e5ef2afc67a184395daf8f97f74a1</id>
<content type='text'>
[ Upstream commit 75b5ab134bb5f657ef7979a59106dce0657e8d87 ]

Clang enables -Wenum-enum-conversion and -Wenum-compare-conditional
under -Wenum-conversion. A recent change in Clang strengthened these
warnings and they appear frequently in common builds, primarily due to
several instances in common headers but there are quite a few drivers
that have individual instances as well.

  include/linux/vmstat.h:508:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
    508 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
        |                            ~~~~~~~~~~~~~~~~~~~~~ ^
    509 |                            item];
        |                            ~~~~

  drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c:955:24: warning: conditional expression between different enumeration types ('enum iwl_mac_beacon_flags' and 'enum iwl_mac_beacon_flags_v1') [-Wenum-compare-conditional]
    955 |                 flags |= is_new_rate ? IWL_MAC_BEACON_CCK
        |                                      ^ ~~~~~~~~~~~~~~~~~~
    956 |                           : IWL_MAC_BEACON_CCK_V1;
        |                             ~~~~~~~~~~~~~~~~~~~~~
  drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c:1120:21: warning: conditional expression between different enumeration types ('enum iwl_mac_beacon_flags' and 'enum iwl_mac_beacon_flags_v1') [-Wenum-compare-conditional]
   1120 |                                                0) &gt; 10 ?
        |                                                        ^
   1121 |                         IWL_MAC_BEACON_FILS :
        |                         ~~~~~~~~~~~~~~~~~~~
   1122 |                         IWL_MAC_BEACON_FILS_V1;
        |                         ~~~~~~~~~~~~~~~~~~~~~~

Doing arithmetic between or returning two different types of enums could
be a bug, so each of the instance of the warning needs to be evaluated.
Unfortunately, as mentioned above, there are many instances of this
warning in many different configurations, which can break the build when
CONFIG_WERROR is enabled.

To avoid introducing new instances of the warnings while cleaning up the
disruption for the majority of users, disable these warnings for the
default build while leaving them on for W=1 builds.

Cc: stable@vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/2002
Link: https://github.com/llvm/llvm-project/commit/8c2ae42b3e1c6aa7c18f873edcebff7c0b45a37e
Acked-by: Yonghong Song &lt;yonghong.song@linux.dev&gt;
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 75b5ab134bb5f657ef7979a59106dce0657e8d87 ]

Clang enables -Wenum-enum-conversion and -Wenum-compare-conditional
under -Wenum-conversion. A recent change in Clang strengthened these
warnings and they appear frequently in common builds, primarily due to
several instances in common headers but there are quite a few drivers
that have individual instances as well.

  include/linux/vmstat.h:508:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
    508 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
        |                            ~~~~~~~~~~~~~~~~~~~~~ ^
    509 |                            item];
        |                            ~~~~

  drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c:955:24: warning: conditional expression between different enumeration types ('enum iwl_mac_beacon_flags' and 'enum iwl_mac_beacon_flags_v1') [-Wenum-compare-conditional]
    955 |                 flags |= is_new_rate ? IWL_MAC_BEACON_CCK
        |                                      ^ ~~~~~~~~~~~~~~~~~~
    956 |                           : IWL_MAC_BEACON_CCK_V1;
        |                             ~~~~~~~~~~~~~~~~~~~~~
  drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c:1120:21: warning: conditional expression between different enumeration types ('enum iwl_mac_beacon_flags' and 'enum iwl_mac_beacon_flags_v1') [-Wenum-compare-conditional]
   1120 |                                                0) &gt; 10 ?
        |                                                        ^
   1121 |                         IWL_MAC_BEACON_FILS :
        |                         ~~~~~~~~~~~~~~~~~~~
   1122 |                         IWL_MAC_BEACON_FILS_V1;
        |                         ~~~~~~~~~~~~~~~~~~~~~~

Doing arithmetic between or returning two different types of enums could
be a bug, so each of the instance of the warning needs to be evaluated.
Unfortunately, as mentioned above, there are many instances of this
warning in many different configurations, which can break the build when
CONFIG_WERROR is enabled.

To avoid introducing new instances of the warnings while cleaning up the
disruption for the majority of users, disable these warnings for the
default build while leaving them on for W=1 builds.

Cc: stable@vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/2002
Link: https://github.com/llvm/llvm-project/commit/8c2ae42b3e1c6aa7c18f873edcebff7c0b45a37e
Acked-by: Yonghong Song &lt;yonghong.song@linux.dev&gt;
Signed-off-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kconfig: fix infinite loop when expanding a macro at the end of file</title>
<updated>2024-03-26T22:22:42+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2024-02-02T15:57:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d0687545f89d410b42ed84a8cb089bd670e0a5cf'/>
<id>d0687545f89d410b42ed84a8cb089bd670e0a5cf</id>
<content type='text'>
[ Upstream commit af8bbce92044dc58e4cc039ab94ee5d470a621f5 ]

A macro placed at the end of a file with no newline causes an infinite
loop.

[Test Kconfig]
  $(info,hello)
  \ No newline at end of file

I realized that flex-provided input() returns 0 instead of EOF when it
reaches the end of a file.

Fixes: 104daea149c4 ("kconfig: reference environment variables directly and remove 'option env='")
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit af8bbce92044dc58e4cc039ab94ee5d470a621f5 ]

A macro placed at the end of a file with no newline causes an infinite
loop.

[Test Kconfig]
  $(info,hello)
  \ No newline at end of file

I realized that flex-provided input() returns 0 instead of EOF when it
reaches the end of a file.

Fixes: 104daea149c4 ("kconfig: reference environment variables directly and remove 'option env='")
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
