| Message ID | ec69cc95a98548c862c22b742936244fdb0c7984.1632813331.git.christophe.leroy@csgroup.eu (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,1/4] mm: Create a new system state and fix core_kernel_text() | expand |
On Tue, 28 Sep 2021 09:15:35 +0200 Christophe Leroy <christophe.leroy@csgroup.eu> wrote: > Commit 7a5da02de8d6 ("locking/lockdep: check for freed initmem in > static_obj()") added arch_is_kernel_initmem_freed() which is supposed > to report whether an object is part of already freed init memory. > > For the time being, the generic version of arch_is_kernel_initmem_freed() > always reports 'false', allthough free_initmem() is generically called > on all architectures. > > Therefore, change the generic version of arch_is_kernel_initmem_freed() > to check whether free_initmem() has been called. If so, then check > if a given address falls into init memory. > > In order to use function init_section_contains(), the fonction is > moved at the end of asm-generic/section.h i386 allmodconfig: In file included from arch/x86/platform/intel-quark/imr.c:28: ./include/asm-generic/sections.h: In function 'arch_is_kernel_initmem_freed': ./include/asm-generic/sections.h:171:6: error: 'system_state' undeclared (first use in this function) 171 | if (system_state < SYSTEM_FREEING_INITMEM) | ^~~~~~~~~~~~ ./include/asm-generic/sections.h:171:6: note: each undeclared identifier is reported only once for each function it appears in ./include/asm-generic/sections.h:171:21: error: 'SYSTEM_FREEING_INITMEM' undeclared (first use in this function) 171 | if (system_state < SYSTEM_FREEING_INITMEM) | ^~~~~~~~~~~~~~~~~~~~~~ I don't think it would be a good idea to include kernel.h from sections.h - it's unclear to me which is the "innermost" of those two. It would be better to uninline arch_is_kernel_initmem_freed(). Surely there's no real reason for inlining it? Anyway, I'll drop the series for now.
diff --git a/include/asm-generic/sections.h b/include/asm-generic/sections.h index d16302d3eb59..13f301239007 100644 --- a/include/asm-generic/sections.h +++ b/include/asm-generic/sections.h @@ -80,20 +80,6 @@ static inline int arch_is_kernel_data(unsigned long addr) } #endif -/* - * Check if an address is part of freed initmem. This is needed on architectures - * with virt == phys kernel mapping, for code that wants to check if an address - * is part of a static object within [_stext, _end]. 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 inline int arch_is_kernel_initmem_freed(unsigned long addr) -{ - return 0; -} -#endif - /** * memory_contains - checks if an object is contained within a memory region * @begin: virtual address of the beginning of the memory region @@ -172,4 +158,21 @@ static inline bool is_kernel_rodata(unsigned long addr) addr < (unsigned long)__end_rodata; } +/* + * Check if an address is part of freed initmem. This is needed on architectures + * with virt == phys kernel mapping, for code that wants to check if an address + * is part of a static object within [_stext, _end]. 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 inline 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 + #endif /* _ASM_GENERIC_SECTIONS_H_ */
Commit 7a5da02de8d6 ("locking/lockdep: check for freed initmem in static_obj()") added arch_is_kernel_initmem_freed() which is supposed to report whether an object is part of already freed init memory. For the time being, the generic version of arch_is_kernel_initmem_freed() always reports 'false', allthough free_initmem() is generically called on all architectures. Therefore, change the generic version of arch_is_kernel_initmem_freed() to check whether free_initmem() has been called. If so, then check if a given address falls into init memory. In order to use function init_section_contains(), the fonction is moved at the end of asm-generic/section.h Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> --- v2: Change to using the new SYSTEM_FREEING_INITMEM state --- include/asm-generic/sections.h | 31 +++++++++++++++++-------------- 1 file changed, 17 insertions(+), 14 deletions(-)