Due to the fact that runtime const ELF sections are named without a
leading period or double underscore, the RSTRIP logic that removes the
static RELA sections from vmlinux fails to identify them. This results
in a situation like below, where some sections that were supposed to get
removed are left behind.
[Nr] Name Type Address Off Size ES Flg Lk Inf Al
[58] runtime_shift_d_hash_shift PROGBITS ffffffff83500f50 2900f50 000014 00 A 0 0 1
[59] .relaruntime_shift_d_hash_shift RELA 0000000000000000 55b6f00 000078 18 I 70 58 8
[60] runtime_ptr_dentry_hashtable PROGBITS ffffffff83500f68 2900f68 000014 00 A 0 0 1
[61] .relaruntime_ptr_dentry_hashtable RELA 0000000000000000 55b6f78 000078 18 I 70 60 8
[62] runtime_ptr_USER_PTR_MAX PROGBITS ffffffff83500f80 2900f80 000238 00 A 0 0 1
[63] .relaruntime_ptr_USER_PTR_MAX RELA 0000000000000000 55b6ff0 000d50 18 I 70 62 8
So tweak the match expression to strip all sections starting with .rel.
While at it, consolidate the logic used by RISC-V, s390 and x86 into a
single shared Makefile library command.
Link: https://lore.kernel.org/all/CAHk-=wjk3ynjomNvFN8jf9A1k=qSc=JFF591W00uXj-qqNUxPQ@mail.gmail.com/
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Tested-by: Charlie Jenkins <charlie@rivosinc.com>
Tested-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The string allocated in sym_warn_unmet_dep() is never freed, leading
to a memory leak when an unmet dependency is detected.
Fixes: f8f69dc0b4 ("kconfig: make unmet dependency warnings readable")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Most 'make *config' commands use .config as the base configuration file.
When .config does not exist, Kconfig tries to load a file listed in
KCONFIG_DEFCONFIG_LIST instead.
However, since commit b75b0a819a ("kconfig: change defconfig_list
option to environment variable"), warning messages have displayed an
incorrect file name in such cases.
Below is a demonstration using Debian Trixie. While loading
/boot/config-6.12.9-amd64, the warning messages incorrectly show .config
as the file name.
With this commit, the correct file name is displayed in warnings.
[Before]
$ rm -f .config
$ make config
#
# using defaults found in /boot/config-6.12.9-amd64
#
.config:6804:warning: symbol value 'm' invalid for FB_BACKLIGHT
.config:9895:warning: symbol value 'm' invalid for ANDROID_BINDER_IPC
[After]
$ rm -f .config
$ make config
#
# using defaults found in /boot/config-6.12.9-amd64
#
/boot/config-6.12.9-amd64:6804:warning: symbol value 'm' invalid for FB_BACKLIGHT
/boot/config-6.12.9-amd64:9895:warning: symbol value 'm' invalid for ANDROID_BINDER_IPC
Fixes: b75b0a819a ("kconfig: change defconfig_list option to environment variable")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
A longstanding issue with genksyms is that it has hidden syntax errors.
For example, genksyms fails to parse the following valid code:
int x, __attribute__((__section__(".init.data")))y;
Here, only 'y' is annotated by the attribute, although I am not aware
of actual uses of this pattern in the kernel tree.
When a syntax error occurs, yyerror() is called. However,
error_with_pos() is a no-op unless the -w option is provided.
You can observe syntax errors by manually passing the -w option.
$ echo 'int x, __attribute__((__section__(".init.data")))y;' | scripts/genksyms/genksyms -w
<stdin>:1: syntax error
This commit allows attributes to be placed between a comma and
init_declarator.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
A longstanding issue with genksyms is that it has hidden syntax errors.
When a syntax error occurs, yyerror() is called. However,
error_with_pos() is a no-op unless the -w option is provided.
You can observe syntax errors by manually passing the -w option.
For example, genksyms fails to parse the following code in
arch/arm64/lib/xor-neon.c:
static inline uint64x2_t eor3(uint64x2_t p, uint64x2_t q, uint64x2_t r)
{
[ snip ]
}
The syntax error occurs because genksyms does not recognize the
uint64x2_t keyword.
This commit adds support for builtin types described in Arm Neon
Intrinsics Reference.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
A longstanding issue with genksyms is that it has hidden syntax errors.
When a syntax error occurs, yyerror() is called. However,
error_with_pos() is a no-op unless the -w option is provided.
You can observe syntax errors by manually passing the -w option.
For example, with CONFIG_MODVERSIONS=y on v6.13-rc1:
$ make -s KCFLAGS=-D__GENKSYMS__ fs/lockd/svc.i
$ cat fs/lockd/svc.i | scripts/genksyms/genksyms -w
[ snip ]
./include/net/addrconf.h:35: syntax error
The syntax error occurs in the following code in include/net/addrconf.h:
union __packed {
[ snip ]
};
The issue arises from __packed, which is defined as
__attribute__((__packed__)), immediately after the 'union' keyword.
This commit allows the 'union' keyword to be followed by attributes.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
A longstanding issue with genksyms is that it has hidden syntax errors.
When a syntax error occurs, yyerror() is called. However,
error_with_pos() is a no-op unless the -w option is provided.
You can observe syntax errors by manually passing the -w option.
For example, with CONFIG_MODVERSIONS=y on v6.13-rc1:
$ make -s KCFLAGS=-D__GENKSYMS__ arch/x86/kernel/cpu/mshyperv.i
$ cat arch/x86/kernel/cpu/mshyperv.i | scripts/genksyms/genksyms -w
[ snip ]
./arch/x86/include/asm/svm.h:122: syntax error
The syntax error occurs in the following code in arch/x86/include/asm/svm.h:
struct __attribute__ ((__packed__)) vmcb_control_area {
[ snip ]
};
The issue arises from __attribute__ immediately after the 'struct'
keyword.
This commit allows the 'struct' keyword to be followed by attributes.
The lexer must be adjusted because dont_want_brace_phase should not be
decremented while processing attributes.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
A longstanding issue with genksyms is that it has hidden syntax errors.
When a syntax error occurs, yyerror() is called. However,
error_with_pos() is a no-op unless the -w option is provided.
You can observe syntax errors by manually passing the -w option.
For example, with CONFIG_MODVERSIONS=y on v6.13-rc1:
$ make -s KCFLAGS=-D__GENKSYMS__ kernel/module/main.i
$ cat kernel/module/main.i | scripts/genksyms/genksyms -w
[ snip ]
kernel/module/main.c:97: syntax error
The syntax error occurs in the following code in kernel/module/main.c:
static void __mod_update_bounds(enum mod_mem_type type __maybe_unused, void *base,
unsigned int size, struct mod_tree_root *tree)
{
[ snip ]
}
The issue arises from __maybe_unused, which is defined as
__attribute__((__unused__)).
This commit allows direct_abstract_declarator to be followed with
attributes.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
A longstanding issue with genksyms is that it has hidden syntax errors.
When a syntax error occurs, yyerror() is called. However,
error_with_pos() is a no-op unless the -w option is provided.
You can observe syntax errors by manually passing the -w option.
For example, with CONFIG_MODVERSIONS=y on v6.13-rc1:
$ make -s KCFLAGS=-D__GENKSYMS__ drivers/acpi/prmt.i
$ cat drivers/acpi/prmt.i | scripts/genksyms/genksyms -w
[ snip ]
drivers/acpi/prmt.c:56: syntax error
The syntax error occurs in the following code in drivers/acpi/prmt.c:
struct prm_handler_info {
[ snip ]
efi_status_t (__efiapi *handler_addr)(u64, void *);
[ snip ]
};
The issue arises from __efiapi, which is defined as either
__attribute__((ms_abi)) or __attribute__((regparm(0))).
This commit allows nested_declarator to be prefixed with attributes.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
A longstanding issue with genksyms is that it has hidden syntax errors.
When a syntax error occurs, yyerror() is called. However,
error_with_pos() is a no-op unless the -w option is provided.
You can observe syntax errors by manually passing the -w option.
For example, with CONFIG_MODVERSIONS=y on v6.13-rc1:
$ make -s KCFLAGS=-D__GENKSYMS__ init/main.i
$ cat init/main.i | scripts/genksyms/genksyms -w
[ snip ]
./include/linux/efi.h:1225: syntax error
The syntax error occurs in the following code in include/linux/efi.h:
efi_status_t
efi_call_acpi_prm_handler(efi_status_t (__efiapi *handler_addr)(u64, void *),
u64 param_buffer_addr, void *context);
The issue arises from __efiapi, which is defined as either
__attribute__((ms_abi)) or __attribute__((regparm(0))).
This commit allows abstract_declarator to be prefixed with attributes.
To avoid conflicts, I tweaked the rule for decl_specifier_seq. Due to
this change, a standalone attribute cannot become decl_specifier_seq.
Otherwise, I do not know how to resolve the conflicts.
The following code, which was previously accepted by genksyms, will now
result in a syntax error:
void my_func(__attribute__((unused))x);
I do not think it is a big deal because GCC also fails to parse it.
$ echo 'void my_func(__attribute__((unused))x);' | gcc -c -x c -
<stdin>:1:37: error: unknown type name 'x'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
The __attribute__ keyword can appear in more contexts than 'const' or
'volatile'.
To avoid grammatical conflicts with future changes, ATTRIBUTE_PHRASE
should not be reduced into type_qualifier.
No functional changes are intended.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
I believe the missing action here is a bug.
For rules with no explicit action, the following default is used:
{ $$ = $1; }
However, in this case, $1 is the value of attribute_opt itself. As a
result, the value of attribute_opt is always NULL.
The following test code demonstrates inconsistent behavior.
int x __attribute__((__aligned__(4)));
int y __attribute__((__aligned__(4))) = 0;
The attribute is recorded only when followed by an initializer.
This commit adds the correct action to propagate the value of the
ATTRIBUTE_PHRASE token.
With this change, the attribute in the example above is consistently
recorded for both 'x' and 'y'.
[Before]
$ cat <<EOF | scripts/genksyms/genksyms -d
int x __attribute__((__aligned__(4)));
int y __attribute__((__aligned__(4))) = 0;
EOF
Defn for type0 x == <int x >
Defn for type0 y == <int y __attribute__ ( ( __aligned__ ( 4 ) ) ) >
Hash table occupancy 2/4096 = 0.000488281
[After]
$ cat <<EOF | scripts/genksyms/genksyms -d
int x __attribute__((__aligned__(4)));
int y __attribute__((__aligned__(4))) = 0;
EOF
Defn for type0 x == <int x __attribute__ ( ( __aligned__ ( 4 ) ) ) >
Defn for type0 y == <int y __attribute__ ( ( __aligned__ ( 4 ) ) ) >
Hash table occupancy 2/4096 = 0.000488281
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
Similar to the previous commit, this change makes the parser logic a
little more accurate.
Currently, genksyms accepts the following invalid code:
struct foo {
int (*callback)(int)(int)(int);
};
A direct-declarator should not recursively absorb multiple
( parameter-type-list ) constructs.
In the example above, (*callback) should be followed by at most one
(int).
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
While there is no more grammatical ambiguity in genksyms, the parser
logic is still inaccurate.
For example, genksyms accepts the following invalid C code:
void my_func(int ()(int));
This should result in a syntax error because () cannot be reduced to
<direct-abstract-declarator>.
( <abstract-declarator> ) can be reduced, but <abstract-declarator>
must not be empty in the following grammar from K&R [1]:
<direct-abstract-declarator> ::= ( <abstract-declarator> )
| {<direct-abstract-declarator>}? [ {<constant-expression>}? ]
| {<direct-abstract-declarator>}? ( {<parameter-type-list>}? )
Furthermore, genksyms accepts the following weird code:
void my_func(int (*callback)(int)(int)(int));
The parser allows <direct-abstract-declarator> to recursively absorb
multiple ( {<parameter-type-list>}? ), but this behavior is incorrect.
In the example above, (*callback) should be followed by at most one
(int).
[1]: https://cs.wmich.edu/~gupta/teaching/cs4850/sumII06/The%20syntax%20of%20C%20in%20Backus-Naur%20form.htm
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
This workaround was introduced for suppressing the reduce/reduce conflict
warnings because the %expect-rr directive, which is applicable only to GLR
parsers, cannot be used for genksyms.
Since there are no longer any conflicts, this Makefile hack is now
unnecessary.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
The genksyms parser has ambiguities in its grammar, which are currently
suppressed by a workaround in scripts/genksyms/Makefile.
Building genksyms with W=1 generates the following warnings:
YACC scripts/genksyms/parse.tab.[ch]
scripts/genksyms/parse.y: warning: 3 shift/reduce conflicts [-Wconflicts-sr]
scripts/genksyms/parse.y: note: rerun with option '-Wcounterexamples' to generate conflict counterexamples
The ambiguity arises when decl_specifier_seq is followed by '(' because
the following two interpretations are possible:
- decl_specifier_seq direct_abstract_declarator '(' parameter_declaration_clause ')'
- decl_specifier_seq '(' abstract_declarator ')'
This issue occurs because the current parser allows an empty string to
be reduced to direct_abstract_declarator, which is incorrect.
K&R [1] explains the correct grammar:
<parameter-declaration> ::= {<declaration-specifier>}+ <declarator>
| {<declaration-specifier>}+ <abstract-declarator>
| {<declaration-specifier>}+
<abstract-declarator> ::= <pointer>
| <pointer> <direct-abstract-declarator>
| <direct-abstract-declarator>
<direct-abstract-declarator> ::= ( <abstract-declarator> )
| {<direct-abstract-declarator>}? [ {<constant-expression>}? ]
| {<direct-abstract-declarator>}? ( {<parameter-type-list>}? )
This commit resolves all remaining conflicts.
We need to consider the difference between the following two examples:
[Example 1] ( <abstract-declarator> ) can become <direct-abstract-declarator>
void my_func(int (foo));
... is equivalent to:
void my_func(int foo);
[Example 2] ( <parameter-type-list> ) can become <direct-abstract-declarator>
typedef int foo;
void my_func(int (foo));
... is equivalent to:
void my_func(int (*callback)(int));
Please note that the function declaration is identical in both examples,
but the preceding typedef creates the distinction. I introduced a new
term, open_paren, to enable the type lookup immediately after the '('
token. Without this, we cannot distinguish between [Example 1] and
[Example 2].
[1]: https://cs.wmich.edu/~gupta/teaching/cs4850/sumII06/The%20syntax%20of%20C%20in%20Backus-Naur%20form.htm
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
The genksyms parser has ambiguities in its grammar, which are currently
suppressed by a workaround in scripts/genksyms/Makefile.
Building genksyms with W=1 generates the following warnings:
YACC scripts/genksyms/parse.tab.[ch]
scripts/genksyms/parse.y: warning: 9 shift/reduce conflicts [-Wconflicts-sr]
scripts/genksyms/parse.y: warning: 5 reduce/reduce conflicts [-Wconflicts-rr]
scripts/genksyms/parse.y: note: rerun with option '-Wcounterexamples' to generate conflict counterexamples
The comment in the parser describes the current problem:
/* This wasn't really a typedef name but an identifier that
shadows one. */
Consider the following simple C code:
typedef int foo;
void my_func(foo foo) {}
In the function parameter list (foo foo), the first 'foo' is a type
specifier (typedef'ed as 'int'), while the second 'foo' is an identifier.
However, the lexer cannot distinguish between the two. Since 'foo' is
already typedef'ed, the lexer returns TYPE for both instances, instead
of returning IDENT for the second one.
To support shadowed identifiers, TYPE can be reduced to either a
simple_type_specifier or a direct_abstract_declarator, which creates
a grammatical ambiguity.
Without analyzing the grammar context, it is very difficult to resolve
this correctly.
This commit introduces a flag, dont_want_type_specifier, which allows
the parser to inform the lexer whether an identifier is expected. When
dont_want_type_specifier is true, the type lookup is suppressed, and
the lexer returns IDENT regardless of any preceding typedef.
After this commit, only 3 shift/reduce conflicts will remain.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <n.schier@avm.de>
When running the sign script the kernel is within the source directory
of external modules. This caused issues when the kernel uses relative
paths, like:
make[5]: Entering directory '/build/client/devel/kernel/work/linux-2.6'
make[6]: Entering directory '/build/client/devel/addmodules/vtx/work/vtx'
INSTALL /build/client/devel/addmodules/vtx/_/lib/modules/6.13.0-devel+/extra/vtx.ko
SIGN /build/client/devel/addmodules/vtx/_/lib/modules/6.13.0-devel+/extra/vtx.ko
/bin/sh: 1: scripts/sign-file: not found
DEPMOD /build/client/devel/addmodules/vtx/_/lib/modules/6.13.0-devel+
Working around it by using absolute pathes here.
Fixes: 13b25489b6 ("kbuild: change working directory to external module directory with M=")
Signed-off-by: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
If you know that your kernel modules will only ever be loaded by a newer
kernel, you can disable BASIC_MODVERSIONS to save space. This also
allows easy creation of test modules to see how tooling will respond to
modules that only have the new format.
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Generate both the existing modversions format and the new extended one
when running modpost. Presence of this metadata in the final .ko is
guarded by CONFIG_EXTENDED_MODVERSIONS.
We no longer generate an error on long symbols in modpost if
CONFIG_EXTENDED_MODVERSIONS is set, as they can now be appropriately
encoded in the extended section. These symbols will be skipped in the
previous encoding. An error will still be generated if
CONFIG_EXTENDED_MODVERSIONS is not set.
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
When MODVERSIONS is enabled, allow selecting gendwarfksyms as the
implementation, but default to genksyms.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The compiler may choose not to emit type information in DWARF for
external symbols. Clang, for example, does this for symbols not
defined in the current TU.
To provide a way to work around this issue, add support for
__gendwarfksyms_ptr_<symbol> pointers that force the compiler to emit
the necessary type information in DWARF also for the missing symbols.
Example usage:
#define GENDWARFKSYMS_PTR(sym) \
static typeof(sym) *__gendwarfksyms_ptr_##sym __used \
__section(".discard.gendwarfksyms") = &sym;
extern int external_symbol(void);
GENDWARFKSYMS_PTR(external_symbol);
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
