merge of '88dd6a801655485b76bb6d591c1f763d51ff47b8'

     and 'ea2a23cae4f4d939a07f699c39b603c4c2559ad1'

1 files changed, 38 insertions, 0 deletions

diff --git a/packages/linux/linux-2.6.21/misalignment-handling.patch b/packages/linux/linux-2.6.21/misalignment-handling.patch
new file mode 100644
index 0000000000..e6aefb997c
--- /dev/null
+++ b/packages/linux/linux-2.6.21/misalignment-handling.patch
@@ -0,0 +1,38 @@
+Change the default alingment handling to not be silent failure
+Index: linux-2.6.21gum/arch/arm/mm/alignment.c
+===================================================================
+--- linux-2.6.21gum.orig/arch/arm/mm/alignment.c
++++ linux-2.6.21gum/arch/arm/mm/alignment.c
+@@ -797,6 +797,8 @@ static int __init alignment_init(void)
+ 	res->write_proc = proc_alignment_write;
+ #endif
+ 
++	ai_usermode = CONFIG_ALIGNMENT_HANDLING;
++
+ 	hook_fault_code(1, do_alignment, SIGILL, "alignment exception");
+ 	hook_fault_code(3, do_alignment, SIGILL, "alignment exception");
+ 
+Index: linux-2.6.21gum/arch/arm/Kconfig
+===================================================================
+--- linux-2.6.21gum.orig/arch/arm/Kconfig
++++ linux-2.6.21gum/arch/arm/Kconfig
+@@ -709,6 +709,19 @@ config ALIGNMENT_TRAP
+ 	  correct operation of some network protocols. With an IP-only
+ 	  configuration it is safe to say N, otherwise say Y.
+ 
++config ALIGNMENT_HANDLING
++	hex "Userspace alignment trap handling"
++	default "0x3"
++	depends on ALIGNMENT_TRAP
++	help
++	  How should we handle alignment errors in userspace by default?  This is a bitfield where:
++	  0 - silently ignore alignment errors (will lead to unexpected results)
++	  1 - report alignment errors through printk (will lead to unexpected results, but you'll know about them)
++	  2 - fix the alignment and make things work properly (performance degradation for un-aligned code)
++	  4 - raise SIGBUS on alignment traps
++	  A good number to choose is probably either 3 (work slowly but log message) or 5 (log message and SIGBUS).
++	  You can change the behavior at runtime through /proc/cpu/alignment if you have PROC_FS enabled.
++
+ endmenu
+ 
+ menu "Boot options"