From 7c76c813cfc42a7376378a0c4b7250db2eebab81 Mon Sep 17 00:00:00 2001 From: Shyam Saini Date: Thu, 27 Feb 2025 10:49:29 -0800 Subject: 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 Signed-off-by: Shyam Saini Link: https://lore.kernel.org/r/20250227184930.34163-4-shyamsaini@linux.microsoft.com Signed-off-by: Petr Pavlu --- include/linux/module.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux/module.h') diff --git a/include/linux/module.h b/include/linux/module.h index d94b196d5a34e..b3329110d6686 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -162,6 +162,8 @@ extern void cleanup_module(void); #define __INITRODATA_OR_MODULE __INITRODATA #endif /*CONFIG_MODULES*/ +struct module_kobject *lookup_or_create_module_kobject(const char *name); + /* Generic info of form tag = "info" */ #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info) -- cgit v1.2.3 From 872df34d7c51a79523820ea6a14860398c639b87 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 14 Oct 2024 10:05:48 -0700 Subject: 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) Signed-off-by: Pawan Gupta Signed-off-by: Dave Hansen Reviewed-by: Alexandre Chartre --- include/linux/module.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux/module.h') diff --git a/include/linux/module.h b/include/linux/module.h index b3329110d6686..8050f77c3b64f 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -586,6 +586,11 @@ struct module { atomic_t refcnt; #endif +#ifdef CONFIG_MITIGATION_ITS + int its_num_pages; + void **its_page_array; +#endif + #ifdef CONFIG_CONSTRUCTORS /* Constructor functions. */ ctor_fn_t *ctors; -- cgit v1.2.3