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author | Don Zickus <dzickus@redhat.com> | 2012-06-06 10:05:42 -0400 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2012-06-08 12:19:27 +0200 |
commit | eeaaa96a3a2134a174100afd129bb0891d05f4b2 (patch) | |
tree | bdb04df0af81d196f28446c0d985aef6cf0dca97 /arch/x86 | |
parent | d5d2d2eea84b0d8450b082edbc3dbde41fb8bfd8 (diff) | |
download | linux-eeaaa96a3a2134a174100afd129bb0891d05f4b2.tar.bz2 |
x86/nmi: Fix section mismatch warnings on 32-bit
It was reported that compiling for 32-bit caused a bunch of
section mismatch warnings:
VDSOSYM arch/x86/vdso/vdso32-syms.lds
LD arch/x86/vdso/built-in.o
LD arch/x86/built-in.o
WARNING: arch/x86/built-in.o(.data+0x5af0): Section mismatch in
reference from the variable test_nmi_ipi_callback_na.10451 to
the function .init.text:test_nmi_ipi_callback() [...]
WARNING: arch/x86/built-in.o(.data+0x5b04): Section mismatch in
reference from the variable nmi_unk_cb_na.10399 to the function
.init.text:nmi_unk_cb() The variable nmi_unk_cb_na.10399
references the function __init nmi_unk_cb() [...]
Both of these are attributed to the internal representation of
the nmiaction struct created during register_nmi_handler. The
reason for this is that those structs are not defined in the
init section whereas the rest of the code in nmi_selftest.c is.
To resolve this, I created a new #define,
register_nmi_handler_initonly, that tags the struct as
__initdata to resolve the mismatch. This #define should only be
used in rare situations where the register/unregister is called
during init of the kernel.
Big thanks to Jan Beulich for decoding this for me as I didn't
have a clue what was going on.
Reported-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Tested-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1338991542-23000-1-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/include/asm/nmi.h | 14 | ||||
-rw-r--r-- | arch/x86/kernel/nmi_selftest.c | 4 |
2 files changed, 16 insertions, 2 deletions
diff --git a/arch/x86/include/asm/nmi.h b/arch/x86/include/asm/nmi.h index 0e3793b821ef..dc580c42851c 100644 --- a/arch/x86/include/asm/nmi.h +++ b/arch/x86/include/asm/nmi.h @@ -54,6 +54,20 @@ struct nmiaction { __register_nmi_handler((t), &fn##_na); \ }) +/* + * For special handlers that register/unregister in the + * init section only. This should be considered rare. + */ +#define register_nmi_handler_initonly(t, fn, fg, n) \ +({ \ + static struct nmiaction fn##_na __initdata = { \ + .handler = (fn), \ + .name = (n), \ + .flags = (fg), \ + }; \ + __register_nmi_handler((t), &fn##_na); \ +}) + int __register_nmi_handler(unsigned int, struct nmiaction *); void unregister_nmi_handler(unsigned int, const char *); diff --git a/arch/x86/kernel/nmi_selftest.c b/arch/x86/kernel/nmi_selftest.c index e31bf8d5c4d2..149b8d9c6ad4 100644 --- a/arch/x86/kernel/nmi_selftest.c +++ b/arch/x86/kernel/nmi_selftest.c @@ -42,7 +42,7 @@ static int __init nmi_unk_cb(unsigned int val, struct pt_regs *regs) static void __init init_nmi_testsuite(void) { /* trap all the unknown NMIs we may generate */ - register_nmi_handler(NMI_UNKNOWN, nmi_unk_cb, 0, "nmi_selftest_unk"); + register_nmi_handler_initonly(NMI_UNKNOWN, nmi_unk_cb, 0, "nmi_selftest_unk"); } static void __init cleanup_nmi_testsuite(void) @@ -64,7 +64,7 @@ static void __init test_nmi_ipi(struct cpumask *mask) { unsigned long timeout; - if (register_nmi_handler(NMI_LOCAL, test_nmi_ipi_callback, + if (register_nmi_handler_initonly(NMI_LOCAL, test_nmi_ipi_callback, NMI_FLAG_FIRST, "nmi_selftest")) { nmi_fail = FAILURE; return; |