user/sven/linux.git/include/linux/module.h, branch v6.15.7

x86/its: move its_pages array to struct mod_arch_specific

2025-06-27T10:13:33Z

commit 0b0cae7119a0ec9449d7261b5e672a5fed765068 upstream. The of pages with ITS thunks allocated for modules are tracked by an array in 'struct module'. Since this is very architecture specific data structure, move it to 'struct mod_arch_specific'. No functional changes. Fixes: 872df34d7c51 ("x86/its: Use dynamic thunks for indirect branches") Suggested-by: Peter Zijlstra (Intel) Signed-off-by: Mike Rapoport (Microsoft) Signed-off-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20250603111446.2609381-4-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman

x86/its: Use dynamic thunks for indirect branches

2025-05-09T20:36:58Z

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) Signed-off-by: Pawan Gupta Signed-off-by: Dave Hansen Reviewed-by: Alexandre Chartre

kernel: globalize lookup_or_create_module_kobject()

2025-04-16T12:54:53Z

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 Signed-off-by: Shyam Saini Link: https://lore.kernel.org/r/20250227184930.34163-4-shyamsaini@linux.microsoft.com Signed-off-by: Petr Pavlu

Merge tag 'trace-ringbuffer-v6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2025-03-31T20:37:22Z

Pull ring-buffer updates from Steven Rostedt: - Restructure the persistent memory to have a "scratch" area Instead of hard coding the KASLR offset in the persistent memory by the ring buffer, push that work up to the callers of the persistent memory as they are the ones that need this information. The offsets and such is not important to the ring buffer logic and it should not be part of that. A scratch pad is now created when the caller allocates a ring buffer from persistent memory by stating how much memory it needs to save. - Allow where modules are loaded to be saved in the new scratch pad Save the addresses of modules when they are loaded into the persistent memory scratch pad. - A new module_for_each_mod() helper function was created With the acknowledgement of the module maintainers a new module helper function was created to iterate over all the currently loaded modules. This has a callback to be called for each module. This is needed for when tracing is started in the persistent buffer and the currently loaded modules need to be saved in the scratch area. - Expose the last boot information where the kernel and modules were loaded The last_boot_info file is updated to print out the addresses of where the kernel "_text" location was loaded from a previous boot, as well as where the modules are loaded. If the buffer is recording the current boot, it only prints "# Current" so that it does not expose the KASLR offset of the currently running kernel. - Allow the persistent ring buffer to be released (freed) To have this in production environments, where the kernel command line can not be changed easily, the ring buffer needs to be freed when it is not going to be used. The memory for the buffer will always be allocated at boot up, but if the system isn't going to enable tracing, the memory needs to be freed. Allow it to be freed and added back to the kernel memory pool. - Allow stack traces to print the function names in the persistent buffer Now that the modules are saved in the persistent ring buffer, if the same modules are loaded, the printing of the function names will examine the saved modules. If the module is found in the scratch area and is also loaded, then it will do the offset shift and use kallsyms to display the function name. If the address is not found, it simply displays the address from the previous boot in hex. * tag 'trace-ringbuffer-v6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Use _text and the kernel offset in last_boot_info tracing: Show last module text symbols in the stacktrace ring-buffer: Remove the unused variable bmeta tracing: Skip update_last_data() if cleared and remove active check for save_mod() tracing: Initialize scratch_size to zero to prevent UB tracing: Fix a compilation error without CONFIG_MODULES tracing: Freeable reserved ring buffer mm/memblock: Add reserved memory release function tracing: Update modules to persistent instances when loaded tracing: Show module names and addresses of last boot tracing: Have persistent trace instances save module addresses module: Add module_for_each_mod() function tracing: Have persistent trace instances save KASLR offset ring-buffer: Add ring_buffer_meta_scratch() ring-buffer: Add buffer meta data for persistent ring buffer ring-buffer: Use kaslr address instead of text delta ring-buffer: Fix bytes_dropped calculation issue

Merge tag 'modules-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux

2025-03-30T22:44:36Z

Pull modules updates from Petr Pavlu: - Use RCU instead of RCU-sched The mix of rcu_read_lock(), rcu_read_lock_sched() and preempt_disable() in the module code and its users has been replaced with just rcu_read_lock() - The rest of changes are smaller fixes and updates * tag 'modules-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux: (32 commits) MAINTAINERS: Update the MODULE SUPPORT section module: Remove unnecessary size argument when calling strscpy() module: Replace deprecated strncpy() with strscpy() params: Annotate struct module_param_attrs with __counted_by() bug: Use RCU instead RCU-sched to protect module_bug_list. static_call: Use RCU in all users of __module_text_address(). kprobes: Use RCU in all users of __module_text_address(). bpf: Use RCU in all users of __module_text_address(). jump_label: Use RCU in all users of __module_text_address(). jump_label: Use RCU in all users of __module_address(). x86: Use RCU in all users of __module_address(). cfi: Use RCU while invoking __module_address(). powerpc/ftrace: Use RCU in all users of __module_text_address(). LoongArch: ftrace: Use RCU in all users of __module_text_address(). LoongArch/orc: Use RCU in all users of __module_address(). arm64: module: Use RCU in all users of __module_text_address(). ARM: module: Use RCU in all users of __module_text_address(). module: Use RCU in all users of __module_text_address(). module: Use RCU in all users of __module_address(). module: Use RCU in search_module_extables(). ...

module: Add module_for_each_mod() function

2025-03-28T12:39:27Z

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 Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Mathieu Desnoyers Cc: Andrew Morton Cc: Sami Tolvanen Cc: Daniel Gomez Cc: linux-modules@vger.kernel.org Link: https://lore.kernel.org/20250305164608.962615966@goodmis.org Acked-by: Petr Pavlu Signed-off-by: Steven Rostedt (Google)

module: Use RCU in find_module_all().

2025-03-10T10:54:44Z

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 Cc: Joe Lawrence Cc: Josh Poimboeuf Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Cc: Miroslav Benes Cc: Petr Mladek Cc: Steven Rostedt Cc: linux-trace-kernel@vger.kernel.org Cc: live-patching@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior Acked-by: Peter Zijlstra (Intel) Reviewed-by: Petr Mladek Link: https://lore.kernel.org/r/20250108090457.512198-7-bigeasy@linutronix.de Signed-off-by: Petr Pavlu

Merge branch 'x86/mm'

2025-02-14T09:32:04Z

Depends on the simplifications from commit 1d7e707af446 ("Revert "x86/module: prepare module loading for ROX allocations of text"") Signed-off-by: Peter Zijlstra

kbuild: keep symbols for symbol_get() even with CONFIG_TRIM_UNUSED_KSYMS

2025-02-05T16:08:58Z

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 Suggested-by: Linus Torvalds Signed-off-by: Masahiro Yamada

module: drop unused module_writable_address()

2025-02-03T10:46:03Z

module_writable_address() is unused and can be removed. Signed-off-by: "Mike Rapoport (Microsoft)" Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20250126074733.1384926-9-rppt@kernel.org