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| author | Guenter Roeck <linux@roeck-us.net> | 2020-01-30 18:11:59 -0800 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2020-03-19 11:58:13 +0100 |
| commit | bac59d18c7018a2fd5e800a1e72a8271bf404977 (patch) | |
| tree | 7d047657b3491b41a1049a2aff514c7ef141b369 /arch/x86/kernel/setup.c | |
| parent | 6f8f0dc980028e98ae339876a8403edae4d20e39 (diff) | |
| download | linux-bac59d18c7018a2fd5e800a1e72a8271bf404977.tar.gz linux-bac59d18c7018a2fd5e800a1e72a8271bf404977.tar.bz2 linux-bac59d18c7018a2fd5e800a1e72a8271bf404977.zip | |
x86/setup: Fix static memory detection
When booting x86 images in qemu, the following warning is seen randomly
if DEBUG_LOCKDEP is enabled.
WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:1119
lockdep_register_key+0xc0/0x100
static_obj() returns true if an address is between _stext and _end.
On x86, this includes the brk memory space. Problem is that this memory
block is not static on x86; its unused portions are released after init
and can be allocated. This results in the observed warning if a lockdep
object is allocated from this memory.
Solve the problem by implementing arch_is_kernel_initmem_freed() for
x86 and have it return true if an address is within the released memory
range.
The same problem was solved for s390 with commit
7a5da02de8d6e ("locking/lockdep: check for freed initmem in static_obj()"),
which introduced arch_is_kernel_initmem_freed().
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200131021159.9178-1-linux@roeck-us.net
Diffstat (limited to 'arch/x86/kernel/setup.c')
| -rw-r--r-- | arch/x86/kernel/setup.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index a74262c71484..e6b545047f38 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -64,7 +64,6 @@ RESERVE_BRK(dmi_alloc, 65536); * at link time, with RESERVE_BRK*() facility reserving additional * chunks. */ -static __initdata unsigned long _brk_start = (unsigned long)__brk_base; unsigned long _brk_end = (unsigned long)__brk_base; |