diff options
Diffstat (limited to 'packages/linux/linux-2.6.21/misalignment-handling.patch')
| -rw-r--r-- | packages/linux/linux-2.6.21/misalignment-handling.patch | 38 |
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" |