sysctl: Enable PARISC "unaligned-trap" to be used cross-arch

PARISC defines /proc/sys/kernel/unaligned-trap to runtime toggle unaligned access emulation. The exact mechanics of enablig/disabling are still arch specific, we can make the sysctl usable by other arches. Signed-off-by: Vineet Gupta <[email protected]> Acked-by: Helge Deller <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Helge Deller <[email protected]> Cc: "Eric W. Biederman" <[email protected]> Cc: Serge Hallyn <[email protected]>
vieko · Feb 15, 2013 · bf14e3b · bf14e3b
1 parent 4d86dfb
commit bf14e3b
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Showing 3 changed files with 14 additions and 0 deletions.
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
@@ -20,6 +20,7 @@ config PARISC
 	select ARCH_HAVE_NMI_SAFE_CMPXCHG
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_STRNCPY_FROM_USER
+	select SYSCTL_ARCH_UNALIGN_ALLOW
 	select HAVE_MOD_ARCH_SPECIFIC
 	select MODULES_USE_ELF_RELA
 	select CLONE_BACKWARDS

diff --git a/init/Kconfig b/init/Kconfig
@@ -1232,6 +1232,14 @@ config SYSCTL_EXCEPTION_TRACE
 	help
 	  Enable support for /proc/sys/debug/exception-trace.
 
+config SYSCTL_ARCH_UNALIGN_ALLOW
+	bool
+	help
+	  Enable support for /proc/sys/kernel/unaligned-trap
+	  Allows arches to define/use @unaligned_enabled to runtime toggle
+	  the unaligned access emulation.
+	  see arch/parisc/kernel/unaligned.c for reference
+
 config KALLSYMS
 	 bool "Load all symbols for debugging/ksymoops" if EXPERT
 	 default y

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
@@ -157,6 +157,9 @@ extern int sysctl_tsb_ratio;
 
 #ifdef __hppa__
 extern int pwrsw_enabled;
+#endif
+
+#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
 extern int unaligned_enabled;
 #endif
 
@@ -545,6 +548,8 @@ static struct ctl_table kern_table[] = {
 	 	.mode		= 0644,
 		.proc_handler	= proc_dointvec,
 	},
+#endif
+#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
 	{
 		.procname	= "unaligned-trap",
 		.data		= &unaligned_enabled,