lockdep patch for 6.1-stable to 6.5-stable
Subsystems (3)
Hi Greg,
would you please queue up this upstream patch:
0a6b58c5cd0d ("lockdep: fix static memory detection even more")
to stable kernels 6.1, 6.4 and 6.5 ?
Thanks,
Helge
From 0a6b58c5cd0dfd7961e725212f0fc8dfc5d96195 Mon Sep 17 00:00:00 2001
From: Helge Deller <[email protected]>
Date: Tue, 15 Aug 2023 00:31:09 +0200
Subject: [PATCH] lockdep: fix static memory detection even more
On the parisc architecture, lockdep reports for all static objects which are in the __initdata section (e.g. "setup_done" in devtmpfs, "kthreadd_done" in init/main.c) this warning:
INFO: trying to register non-static key.
The warning itself is wrong, because those objects are in the __initdata section, but the section itself is on parisc outside of range from _stext to _end, which is why the static_obj() functions returns a wrong answer.
While fixing this issue, I noticed that the whole existing check can be simplified a lot.
Instead of checking against the _stext and _end symbols (which include code areas too) just check for the .data and .bss segments (since we check a data object). This can be done with the existing is_kernel_core_data() macro.
In addition objects in the __initdata section can be checked with init_section_contains(), and is_kernel_rodata() allows keys to be in the _ro_after_init section.
This partly reverts and simplifies commit bac59d18c701 ("x86/setup: Fix static memory detection").
arch/x86/include/asm/sections.h +0 -18
@@ -2,8 +2,6 @@#ifndef _ASM_X86_SECTIONS_H#define _ASM_X86_SECTIONS_H -#define arch_is_kernel_initmem_freed arch_is_kernel_initmem_freed -#include <asm-generic/sections.h> #include <asm/extable.h>
@@ -18,20 +16,4 @@ extern char __end_of_kernel_reserve[];extern unsigned long _brk_start, _brk_end; -static inline bool arch_is_kernel_initmem_freed (unsigned long addr) -{ -/* -* If _brk_start has not been cleared, brk allocation is incomplete, -* and we can not make assumptions about its use. -*/ -if (_brk_start) -return 0 ; - -/* -* After brk allocation is complete, space between _brk_end and _end -* is available for allocation. -*/ -return addr >= _brk_end && addr < (unsigned long )&_end; -} -#endif /* _ASM_X86_SECTIONS_H */
kernel/locking/lockdep.c +14 -22
@@ -819,34 +819,26 @@ static int very_verbose(struct lock_class *class)* Is this the address of a static object: */ #ifdef __KERNEL__ -/* -* Check if an address is part of freed initmem. After initmem is freed, -* memory can be allocated from it, and such allocations would then have -* addresses within the range [_stext, _end]. -*/ -#ifndef arch_is_kernel_initmem_freed -static int arch_is_kernel_initmem_freed (unsigned long addr) -{ -if (system_state <SYSTEM_FREEING_INITMEM ) -return 0 ; - -return init_section_contains ((void *)addr,1 ); -} -#endif -static int static_obj (const void *obj) { -unsigned long start = (unsigned long ) &_stext, - end = (unsigned long ) &_end, - addr = (unsigned long ) obj; +unsigned long addr = (unsigned long ) obj; -if (arch_is_kernel_initmem_freed (addr)) -return 0 ; +if (is_kernel_core_data (addr)) +return 1 ; + +/* +* keys are allowed in the __ro_after_init section. +*/ +if (is_kernel_rodata (addr)) +return 1 ;/* -* static variable? +* in initdata section and used during bootup only? +* NOTE: On some platforms the initdata section is +* outside of the _stext ... _end range. */ -if ((addr >= start) && (addr < end)) +if (system_state <SYSTEM_FREEING_INITMEM && +init_section_contains ((void *)addr,1 ))return 1 ;/*
Greg Kroah-Hartman
maintainerQuoted 7 lines · Helge Deller
Hi Greg,
would you please queue up this upstream patch:
0a6b58c5cd0d("lockdep: fix static memory detection even more")to stable kernels 6.1, 6.4 and 6.5 ?
Now queued up, thanks.
greg k-h