x86/its: Use dynamic thunks for indirect branches

ITS mitigation moves the unsafe indirect branches to a safe thunk. This
could degrade the prediction accuracy as the source address of indirect
bran

x86/its: Use dynamic thunks for indirect branches

ITS mitigation moves the unsafe indirect branches to a safe thunk. This
could degrade the prediction accuracy as the source address of indirect
branches becomes same for different execution paths.

To improve the predictions, and hence the performance, assign a separate
thunk for each indirect callsite. This is also a defense-in-depth measure
to avoid indirect branches aliasing with each other.

As an example, 5000 dynamic thunks would utilize around 16 bits of the
address space, thereby gaining entropy. For a BTB that uses
32 bits for indexing, dynamic thunks could provide better prediction
accuracy over fixed thunks.

Have ITS thunks be variable sized and use EXECMEM_MODULE_TEXT such that
they are both more flexible (got to extend them later) and live in 2M TLBs,
just like kernel code, avoiding undue TLB pressure.

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Pawan Gupta <[email protected]>
Signed-off-by: Dave Hansen <[email protected]>
Reviewed-by: Alexandre Chartre <[email protected]>

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kernel: globalize lookup_or_create_module_kobject()

lookup_or_create_module_kobject() is marked as static and __init,
to make it global drop static keyword.
Since this function can be called from no

kernel: globalize lookup_or_create_module_kobject()

lookup_or_create_module_kobject() is marked as static and __init,
to make it global drop static keyword.
Since this function can be called from non-init code, use __modinit
instead of __init, __modinit marker will make it __init if
CONFIG_MODULES is not defined.

Suggested-by: Rasmus Villemoes <[email protected]>
Signed-off-by: Shyam Saini <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Petr Pavlu <[email protected]>

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module: Add module_for_each_mod() function

The tracing system needs a way to save all the currently loaded modules
and their addresses into persistent memory so that it can evaluate the
addresses on

module: Add module_for_each_mod() function

The tracing system needs a way to save all the currently loaded modules
and their addresses into persistent memory so that it can evaluate the
addresses on a reboot from a crash. When the persistent memory trace
starts, it will load the module addresses and names into the persistent
memory. To do so, it will call the module_for_each_mod() function and pass
it a function and data structure to get called on each loaded module. Then
it can record the memory.

This only implements that function.

Cc: Luis Chamberlain <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Sami Tolvanen <[email protected]>
Cc: Daniel Gomez <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/[email protected]
Acked-by: Petr Pavlu <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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module: Use RCU in find_module_all().

The modules list and module::kallsyms can be accessed under RCU
assumption.

Remove module_assert_mutex_or_preempt() from find_module_all() so it can
be used un

module: Use RCU in find_module_all().

The modules list and module::kallsyms can be accessed under RCU
assumption.

Remove module_assert_mutex_or_preempt() from find_module_all() so it can
be used under RCU protection without warnings. Update its callers to use
RCU protection instead of preempt_disable().

Cc: Jiri Kosina <[email protected]>
Cc: Joe Lawrence <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Miroslav Benes <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Petr Pavlu <[email protected]>

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kbuild: keep symbols for symbol_get() even with CONFIG_TRIM_UNUSED_KSYMS

Linus observed that the symbol_request(utf8_data_table) call fails when
CONFIG_UNICODE=y and CONFIG_TRIM_UNUSED_KSYMS=y.

sym

kbuild: keep symbols for symbol_get() even with CONFIG_TRIM_UNUSED_KSYMS

Linus observed that the symbol_request(utf8_data_table) call fails when
CONFIG_UNICODE=y and CONFIG_TRIM_UNUSED_KSYMS=y.

symbol_get() relies on the symbol data being present in the ksymtab for
symbol lookups. However, EXPORT_SYMBOL_GPL(utf8_data_table) is dropped
due to CONFIG_TRIM_UNUSED_KSYMS, as no module references it in this case.

Probably, this has been broken since commit dbacb0ef670d ("kconfig option
for TRIM_UNUSED_KSYMS").

This commit addresses the issue by leveraging modpost. Symbol names
passed to symbol_get() are recorded in the special .no_trim_symbol
section, which is then parsed by modpost to forcibly keep such symbols.
The .no_trim_symbol section is discarded by the linker scripts, so there
is no impact on the size of the final vmlinux or modules.

This commit cannot resolve the issue for direct calls to __symbol_get()
because the symbol name is not known at compile-time.

Although symbol_get() may eventually be deprecated, this workaround
should be good enough meanwhile.

Reported-by: Linus Torvalds <[email protected]>
Suggested-by: Linus Torvalds <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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module: drop unused module_writable_address()

module_writable_address() is unused and can be removed.

Signed-off-by: "Mike Rapoport (Microsoft)" <[email protected]>
Signed-off-by: Peter Zijlstra (Int

module: drop unused module_writable_address()

module_writable_address() is unused and can be removed.

Signed-off-by: "Mike Rapoport (Microsoft)" <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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module: switch to execmem API for remapping as RW and restoring ROX

Instead of using writable copy for module text sections, temporarily remap
the memory allocated from execmem's ROX cache as writab

module: switch to execmem API for remapping as RW and restoring ROX

Instead of using writable copy for module text sections, temporarily remap
the memory allocated from execmem's ROX cache as writable and restore its
ROX permissions after the module is formed.

This will allow removing nasty games with writable copy in alternatives
patching on x86.

Signed-off-by: "Mike Rapoport (Microsoft)" <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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module: Constify 'struct module_attribute'

These structs are never modified, move them to read-only memory.
This makes the API clearer and also prepares for the constification of
'struct attribute'

module: Constify 'struct module_attribute'

These structs are never modified, move them to read-only memory.
This makes the API clearer and also prepares for the constification of
'struct attribute' itself.

While at it, also constify 'modinfo_attrs_count'.

Signed-off-by: Thomas Weißschuh <[email protected]>
Reviewed-by: Petr Pavlu <[email protected]>
Link: https://lore.kernel.org/r/20241216-sysfs-const-attr-module-v1-3-3790b53e0abf@weissschuh.net
Signed-off-by: Petr Pavlu <[email protected]>

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module: Handle 'struct module_version_attribute' as const

The structure is always read-only due to its placement in the read-only
section __modver. Reflect this at its usage sites.
Also prepare for

module: Handle 'struct module_version_attribute' as const

The structure is always read-only due to its placement in the read-only
section __modver. Reflect this at its usage sites.
Also prepare for the const handling of 'struct module_attribute' itself.

Signed-off-by: Thomas Weißschuh <[email protected]>
Reviewed-by: Petr Pavlu <[email protected]>
Link: https://lore.kernel.org/r/20241216-sysfs-const-attr-module-v1-2-3790b53e0abf@weissschuh.net
Signed-off-by: Petr Pavlu <[email protected]>

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module: fix writing of livepatch relocations in ROX text

A livepatch module can contain a special relocation section
.klp.rela.<objname>.<secname> to apply its relocations at the appropriate
time an

module: fix writing of livepatch relocations in ROX text

A livepatch module can contain a special relocation section
.klp.rela.<objname>.<secname> to apply its relocations at the appropriate
time and to additionally access local and unexported symbols. When
<objname> points to another module, such relocations are processed
separately from the regular module relocation process. For instance, only
when the target <objname> actually becomes loaded.

With CONFIG_STRICT_MODULE_RWX, when the livepatch core decides to apply
these relocations, their processing results in the following bug:

[ 25.827238] BUG: unable to handle page fault for address: 00000000000012ba
[ 25.827819] #PF: supervisor read access in kernel mode
[ 25.828153] #PF: error_code(0x0000) - not-present page
[ 25.828588] PGD 0 P4D 0
[ 25.829063] Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
[ 25.829742] CPU: 2 UID: 0 PID: 452 Comm: insmod Tainted: G O K 6.13.0-rc4-00078-g059dd502b263 #7820
[ 25.830417] Tainted: [O]=OOT_MODULE, [K]=LIVEPATCH
[ 25.830768] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-20220807_005459-localhost 04/01/2014
[ 25.831651] RIP: 0010:memcmp+0x24/0x60
[ 25.832190] Code: [...]
[ 25.833378] RSP: 0018:ffffa40b403a3ae8 EFLAGS: 00000246
[ 25.833637] RAX: 0000000000000000 RBX: ffff93bc81d8e700 RCX: ffffffffc0202000
[ 25.834072] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 00000000000012ba
[ 25.834548] RBP: ffffa40b403a3b68 R08: ffffa40b403a3b30 R09: 0000004a00000002
[ 25.835088] R10: ffffffffffffd222 R11: f000000000000000 R12: 0000000000000000
[ 25.835666] R13: ffffffffc02032ba R14: ffffffffc007d1e0 R15: 0000000000000004
[ 25.836139] FS: 00007fecef8c3080(0000) GS:ffff93bc8f900000(0000) knlGS:0000000000000000
[ 25.836519] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 25.836977] CR2: 00000000000012ba CR3: 0000000002f24000 CR4: 00000000000006f0
[ 25.837442] Call Trace:
[ 25.838297] <TASK>
[ 25.841083] __write_relocate_add.constprop.0+0xc7/0x2b0
[ 25.841701] apply_relocate_add+0x75/0xa0
[ 25.841973] klp_write_section_relocs+0x10e/0x140
[ 25.842304] klp_write_object_relocs+0x70/0xa0
[ 25.842682] klp_init_object_loaded+0x21/0xf0
[ 25.842972] klp_enable_patch+0x43d/0x900
[ 25.843572] do_one_initcall+0x4c/0x220
[ 25.844186] do_init_module+0x6a/0x260
[ 25.844423] init_module_from_file+0x9c/0xe0
[ 25.844702] idempotent_init_module+0x172/0x270
[ 25.845008] __x64_sys_finit_module+0x69/0xc0
[ 25.845253] do_syscall_64+0x9e/0x1a0
[ 25.845498] entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 25.846056] RIP: 0033:0x7fecef9eb25d
[ 25.846444] Code: [...]
[ 25.847563] RSP: 002b:00007ffd0c5d6de8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[ 25.848082] RAX: ffffffffffffffda RBX: 000055b03f05e470 RCX: 00007fecef9eb25d
[ 25.848456] RDX: 0000000000000000 RSI: 000055b001e74e52 RDI: 0000000000000003
[ 25.848969] RBP: 00007ffd0c5d6ea0 R08: 0000000000000040 R09: 0000000000004100
[ 25.849411] R10: 00007fecefac7b20 R11: 0000000000000246 R12: 000055b001e74e52
[ 25.849905] R13: 0000000000000000 R14: 000055b03f05e440 R15: 0000000000000000
[ 25.850336] </TASK>
[ 25.850553] Modules linked in: deku(OK+) uinput
[ 25.851408] CR2: 00000000000012ba
[ 25.852085] ---[ end trace 0000000000000000 ]---

The problem is that the .klp.rela.<objname>.<secname> relocations are
processed after the module was already formed and mod->rw_copy was reset.
However, the code in __write_relocate_add() calls
module_writable_address() which translates the target address 'loc' still
to 'loc + (mem->rw_copy - mem->base)', with mem->rw_copy now being 0.

Fix the problem by returning directly 'loc' in module_writable_address()
when the module is already formed. Function __write_relocate_add() knows
to use text_poke() in such a case.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 0c133b1e78cd ("module: prepare to handle ROX allocations for text")
Signed-off-by: Petr Pavlu <[email protected]>
Reported-by: Marek Maslanka <[email protected]>
Closes: https://lore.kernel.org/linux-modules/CAGcaFA2hdThQV6mjD_1_U+GNHThv84+MQvMWLgEuX+LVbAyDxg@mail.gmail.com/
Reviewed-by: Petr Mladek <[email protected]>
Tested-by: Petr Mladek <[email protected]>
Cc: Joe Lawrence <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Petr Mladek <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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module: get symbol CRC back to unsigned

Commit 71810db27c1c ("modversions: treat symbol CRCs as 32 bit
quantities") changed the CRC fields to s32 because the __kcrctab and
__kcrctab_gpl sections con

module: get symbol CRC back to unsigned

Commit 71810db27c1c ("modversions: treat symbol CRCs as 32 bit
quantities") changed the CRC fields to s32 because the __kcrctab and
__kcrctab_gpl sections contained relative references to the actual
CRC values stored in the .rodata section when CONFIG_MODULE_REL_CRCS=y.

Commit 7b4537199a4a ("kbuild: link symbol CRCs at final link, removing
CONFIG_MODULE_REL_CRCS") removed this complexity. Now, the __kcrctab
and __kcrctab_gpl sections directly contain the CRC values in all cases.

The genksyms tool outputs unsigned 32-bit CRC values, so u32 is preferred
over s32.

No functional changes are intended.

Regardless of this change, the CRC value is assigned to the u32 variable
'crcval' before the comparison, as seen in kernel/module/version.c:

crcval = *crc;

It was previously mandatory (but now optional) in order to avoid sign
extension because the following line previously compared 'unsigned long'
and 's32':

if (versions[i].crc == crcval)
return 1;

versions[i].crc is still 'unsigned long' for backward compatibility.

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Petr Pavlu <[email protected]>

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module: Convert symbol namespace to string literal

Clean up the existing export namespace code along the same lines of
commit 33def8498fdd ("treewide: Convert macro and uses of __section(foo)
to __s

module: Convert symbol namespace to string literal

Clean up the existing export namespace code along the same lines of
commit 33def8498fdd ("treewide: Convert macro and uses of __section(foo)
to __section("foo")") and for the same reason, it is not desired for the
namespace argument to be a macro expansion itself.

Scripted using

git grep -l -e MODULE_IMPORT_NS -e EXPORT_SYMBOL_NS | while read file;
do
awk -i inplace '
/^#define EXPORT_SYMBOL_NS/ {
gsub(/__stringify\(ns\)/, "ns");
print;
next;
}
/^#define MODULE_IMPORT_NS/ {
gsub(/__stringify\(ns\)/, "ns");
print;
next;
}
/MODULE_IMPORT_NS/ {
$0 = gensub(/MODULE_IMPORT_NS\(([^)]*)\)/, "MODULE_IMPORT_NS(\"\\1\")", "g");
}
/EXPORT_SYMBOL_NS/ {
if ($0 ~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+),/) {
if ($0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/ &&
$0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(\)/ &&
$0 !~ /^my/) {
getline line;
gsub(/[[:space:]]*\\$/, "");
gsub(/[[:space:]]/, "", line);
$0 = $0 " " line;
}

$0 = gensub(/(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/,
"\\1(\\2, \"\\3\")", "g");
}
}
{ print }' $file;
done

Requested-by: Masahiro Yamada <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://mail.google.com/mail/u/2/#inbox/FMfcgzQXKWgMmjdFwwdsfgxzKpVHWPlc
Acked-by: Greg KH <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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modpost: rename alias symbol for MODULE_DEVICE_TABLE()

This commit renames the alias symbol, __mod_<type>__<name>_device_table
to __mod_device_table__<type>__<name>.

This change simplifies the code

modpost: rename alias symbol for MODULE_DEVICE_TABLE()

This commit renames the alias symbol, __mod_<type>__<name>_device_table
to __mod_device_table__<type>__<name>.

This change simplifies the code slightly, as there is no longer a need
to check both the prefix and suffix.

Signed-off-by: Masahiro Yamada <[email protected]>

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module: prepare to handle ROX allocations for text

In order to support ROX allocations for module text, it is necessary to
handle modifications to the code, such as relocations and alternatives
patc

module: prepare to handle ROX allocations for text

In order to support ROX allocations for module text, it is necessary to
handle modifications to the code, such as relocations and alternatives
patching, without write access to that memory.

One option is to use text patching, but this would make module loading
extremely slow and will expose executable code that is not finally formed.

A better way is to have memory allocated with ROX permissions contain
invalid instructions and keep a writable, but not executable copy of the
module text. The relocations and alternative patches would be done on the
writable copy using the addresses of the ROX memory. Once the module is
completely ready, the updated text will be copied to ROX memory using text
patching in one go and the writable copy will be freed.

Add support for that to module initialization code and provide necessary
interfaces in execmem.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Mike Rapoport (Microsoft) <[email protected]>
Reviewd-by: Luis Chamberlain <[email protected]>
Tested-by: kdevops <[email protected]>
Cc: Andreas Larsson <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Borislav Petkov (AMD) <[email protected]>
Cc: Brian Cain <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Dinh Nguyen <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Guo Ren <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Johannes Berg <[email protected]>
Cc: John Paul Adrian Glaubitz <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Liam R. Howlett <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Masami Hiramatsu (Google) <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Michal Simek <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Russell King <[email protected]>
Cc: Song Liu <[email protected]>
Cc: Stafford Horne <[email protected]>
Cc: Steven Rostedt (Google) <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Uladzislau Rezki (Sony) <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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module: create weak dependecies

It has been seen that for some network mac drivers (i.e. lan78xx) the
related module for the phy is loaded dynamically depending on the current
hardware. In this case

module: create weak dependecies

It has been seen that for some network mac drivers (i.e. lan78xx) the
related module for the phy is loaded dynamically depending on the current
hardware. In this case, the associated phy is read using mdio bus and then
the associated phy module is loaded during runtime (kernel function
phy_request_driver_module). However, no software dependency is defined, so
the user tools will no be able to get this dependency. For example, if
dracut is used and the hardware is present, lan78xx will be included but no
phy module will be added, and in the next restart the device will not work
from boot because no related phy will be found during initramfs stage.

In order to solve this, we could define a normal 'pre' software dependency
in lan78xx module with all the possible phy modules (there may be some),
but proceeding in that way, all the possible phy modules would be loaded
while only one is necessary.

The idea is to create a new type of dependency, that we are going to call
'weak' to be used only by the user tools that need to detect this situation.
In that way, for example, dracut could check the 'weak' dependency of the
modules involved in order to install these dependencies in initramfs too.
That is, for the commented lan78xx module, defining the 'weak' dependency
with the possible phy modules list, only the necessary phy would be loaded
on demand keeping the same behavior, but all the possible phy modules would
be available from initramfs.

The 'weak' dependency support has been included in kmod:
https://github.com/kmod-project/kmod/commit/05828b4a6e9327a63ef94df544a042b5e9ce4fe7
But, take into account that this can only be used if depmod is new enough.
If it isn't, depmod will have the same behavior as always (keeping backward
compatibility) and the information for the 'weak' dependency will not be
provided.

Signed-off-by: Jose Ignacio Tornos Martinez <[email protected]>
Reviewed-by: Lucas De Marchi <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

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kallsyms: rework symbol lookup return codes

Building with W=1 in some configurations produces a false positive
warning for kallsyms:

kernel/kallsyms.c: In function '__sprint_symbol.isra':
kernel/ka

kallsyms: rework symbol lookup return codes

Building with W=1 in some configurations produces a false positive
warning for kallsyms:

kernel/kallsyms.c: In function '__sprint_symbol.isra':
kernel/kallsyms.c:503:17: error: 'strcpy' source argument is the same as destination [-Werror=restrict]
503 | strcpy(buffer, name);
| ^~~~~~~~~~~~~~~~~~~~

This originally showed up while building with -O3, but later started
happening in other configurations as well, depending on inlining
decisions. The underlying issue is that the local 'name' variable is
always initialized to the be the same as 'buffer' in the called functions
that fill the buffer, which gcc notices while inlining, though it could
see that the address check always skips the copy.

The calling conventions here are rather unusual, as all of the internal
lookup functions (bpf_address_lookup, ftrace_mod_address_lookup,
ftrace_func_address_lookup, module_address_lookup and
kallsyms_lookup_buildid) already use the provided buffer and either return
the address of that buffer to indicate success, or NULL for failure,
but the callers are written to also expect an arbitrary other buffer
to be returned.

Rework the calling conventions to return the length of the filled buffer
instead of its address, which is simpler and easier to follow as well
as avoiding the warning. Leave only the kallsyms_lookup() calling conventions
unchanged, since that is called from 16 different functions and
adapting this would be a much bigger change.

Link: https://lore.kernel.org/lkml/[email protected]/
Link: https://lore.kernel.org/lkml/[email protected]/
Tested-by: Geert Uytterhoeven <[email protected]>
Reviewed-by: Luis Chamberlain <[email protected]>
Acked-by: Steven Rostedt (Google) <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>

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module, bpf: Store BTF base pointer in struct module

...as this will allow split BTF modules with a base BTF
representation (rather than the full vmlinux BTF at time of
BTF encoding) to resolve thei

module, bpf: Store BTF base pointer in struct module

...as this will allow split BTF modules with a base BTF
representation (rather than the full vmlinux BTF at time of
BTF encoding) to resolve their references to kernel types in a
way that is more resilient to small changes in kernel types.

This will allow modules that are not built every time the kernel
is to provide more resilient BTF, rather than have it invalidated
every time BTF ids for core kernel types change.

Fields are ordered to avoid holes in struct module.

Signed-off-by: Alan Maguire <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Reviewed-by: Luis Chamberlain <[email protected]>
Acked-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

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kprobes: remove dependency on CONFIG_MODULES

kprobes depended on CONFIG_MODULES because it has to allocate memory for
code.

Since code allocations are now implemented with execmem, kprobes can be
e

kprobes: remove dependency on CONFIG_MODULES

kprobes depended on CONFIG_MODULES because it has to allocate memory for
code.

Since code allocations are now implemented with execmem, kprobes can be
enabled in non-modular kernels.

Add #ifdef CONFIG_MODULE guards for the code dealing with kprobes inside
modules, make CONFIG_KPROBES select CONFIG_EXECMEM and drop the
dependency of CONFIG_KPROBES on CONFIG_MODULES.

Signed-off-by: Mike Rapoport (IBM) <[email protected]>
Acked-by: Masami Hiramatsu (Google) <[email protected]>
[mcgrof: rebase in light of NEED_TASKS_RCU ]
Signed-off-by: Luis Chamberlain <[email protected]>

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x86/bugs: Rename CONFIG_RETPOLINE => CONFIG_MITIGATION_RETPOLINE

Step 5/10 of the namespace unification of CPU mitigations related Kconfig options.

[ mingo: Converted a few more uses in

x86/bugs: Rename CONFIG_RETPOLINE => CONFIG_MITIGATION_RETPOLINE

Step 5/10 of the namespace unification of CPU mitigations related Kconfig options.

[ mingo: Converted a few more uses in comments/messages as well. ]

Suggested-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Breno Leitao <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Reviewed-by: Ariel Miculas <[email protected]>
Acked-by: Josh Poimboeuf <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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kernel/module: improve documentation for try_module_get()

The sentence "this call will fail if the module is already being
removed" is potentially confusing and may contradict the rest of the
docume

kernel/module: improve documentation for try_module_get()

The sentence "this call will fail if the module is already being
removed" is potentially confusing and may contradict the rest of the
documentation. If one tries to get a module that has already been
removed using a stale pointer, the kernel will crash.

Signed-off-by: Marco Pagani <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

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kunit: add KUNIT_INIT_TABLE to init linker section

Add KUNIT_INIT_TABLE to the INIT_DATA linker section.

Alter the KUnit macros to create init tests:
kunit_test_init_section_suites

Update lib/kuni

kunit: add KUNIT_INIT_TABLE to init linker section

Add KUNIT_INIT_TABLE to the INIT_DATA linker section.

Alter the KUnit macros to create init tests:
kunit_test_init_section_suites

Update lib/kunit/executor.c to run both the suites in KUNIT_TABLE and
KUNIT_INIT_TABLE.

Reviewed-by: David Gow <[email protected]>
Signed-off-by: Rae Moar <[email protected]>
Signed-off-by: Shuah Khan <[email protected]>

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kallsyms: remove unsed API lookup_symbol_attrs

with commit '7878c231dae0 ("slab: remove /proc/slab_allocators")'
lookup_symbol_attrs usage is removed.

Thus removing redundant API.

Signed-off-by: M

kallsyms: remove unsed API lookup_symbol_attrs

with commit '7878c231dae0 ("slab: remove /proc/slab_allocators")'
lookup_symbol_attrs usage is removed.

Thus removing redundant API.

Signed-off-by: Maninder Singh <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

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kallsyms: move module-related functions under correct configs

Functions for searching module kallsyms should have non-empty
definitions only if CONFIG_MODULES=y and CONFIG_KALLSYMS=y. Until now,
onl

kallsyms: move module-related functions under correct configs

Functions for searching module kallsyms should have non-empty
definitions only if CONFIG_MODULES=y and CONFIG_KALLSYMS=y. Until now,
only CONFIG_MODULES check was used for many of these, which may have
caused complilation errors on some configs.

This patch moves all relevant functions under the correct configs.

Fixes: bd5314f8dd2d ("kallsyms, bpf: Move find_kallsyms_symbol_value out of internal header")
Signed-off-by: Viktor Malik <[email protected]>
Reported-by: kernel test robot <[email protected]>
Link: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

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kallsyms: Delete an unused parameter related to {module_}kallsyms_on_each_symbol()

The parameter 'struct module *' in the hook function associated with
{module_}kallsyms_on_each_symbol() is no longe

kallsyms: Delete an unused parameter related to {module_}kallsyms_on_each_symbol()

The parameter 'struct module *' in the hook function associated with
{module_}kallsyms_on_each_symbol() is no longer used. Delete it.

Suggested-by: Petr Mladek <[email protected]>
Signed-off-by: Zhen Lei <[email protected]>
Reviewed-by: Vincenzo Palazzo <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Acked-by: Steven Rostedt (Google) <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

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kallsyms, bpf: Move find_kallsyms_symbol_value out of internal header

Moving find_kallsyms_symbol_value from kernel/module/internal.h to
include/linux/module.h. The reason is that internal.h is not

kallsyms, bpf: Move find_kallsyms_symbol_value out of internal header

Moving find_kallsyms_symbol_value from kernel/module/internal.h to
include/linux/module.h. The reason is that internal.h is not prepared to
be included when CONFIG_MODULES=n. find_kallsyms_symbol_value is used by
kernel/bpf/verifier.c and including internal.h from it (without modules)
leads into a compilation error:

In file included from ../include/linux/container_of.h:5,
from ../include/linux/list.h:5,
from ../include/linux/timer.h:5,
from ../include/linux/workqueue.h:9,
from ../include/linux/bpf.h:10,
from ../include/linux/bpf-cgroup.h:5,
from ../kernel/bpf/verifier.c:7:
../kernel/bpf/../module/internal.h: In function 'mod_find':
../include/linux/container_of.h:20:54: error: invalid use of undefined type 'struct module'
20 | static_assert(__same_type(*(ptr), ((type *)0)->member) || \
| ^~
[...]

This patch fixes the above error.

Fixes: 31bf1dbccfb0 ("bpf: Fix attaching fentry/fexit/fmod_ret/lsm to modules")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Viktor Malik <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Link: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Link: https://lore.kernel.org/bpf/[email protected]

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