The patch titled
Subject: mm: make generic arch_is_kernel_initmem_freed() do what it says
has been added to the -mm tree. Its filename is
mm-make-generic-arch_is_kernel_initmem_freed-do-what-it-says.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-make-generic-arch_is_kernel_initmem_freed-do-what-it-says.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-make-generic-arch_is_kernel_initmem_freed-do-what-it-says.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Subject: mm: make generic arch_is_kernel_initmem_freed() do what it says
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
Link: https://lkml.kernel.org/r/0b55650058a5bf64f7d74781871a1ada2298c8b4.1632491308.git.christophe.leroy@xxxxxxxxxx
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: Gerald Schaefer <gerald.schaefer@xxxxxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/asm-generic/sections.h | 31 +++++++++++++++++--------------
1 file changed, 17 insertions(+), 14 deletions(-)
--- a/include/asm-generic/sections.h~mm-make-generic-arch_is_kernel_initmem_freed-do-what-it-says
+++ a/include/asm-generic/sections.h
@@ -80,20 +80,6 @@ static inline int arch_is_kernel_data(un
}
#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(unsi
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_RUNNING)
+ return 0;
+
+ return init_section_contains((void *)addr, 1);
+}
+#endif
+
#endif /* _ASM_GENERIC_SECTIONS_H_ */
_
Patches currently in -mm which might be from christophe.leroy@xxxxxxxxxx are
mm-make-generic-arch_is_kernel_initmem_freed-do-what-it-says.patch
powerpc-use-generic-version-of-arch_is_kernel_initmem_freed.patch
s390-use-generic-version-of-arch_is_kernel_initmem_freed.patch
