[PATCH] ARM: Do not allow unaligned accesses when CONFIG_ALIGNMENT_TRAP
From: catalin.marinas@arm.com (Catalin Marinas)
Date: 2011-05-23 13:51:30
On Mon, 2011-05-23 at 14:21 +0100, Russell King - ARM Linux wrote:
On Mon, May 23, 2011 at 12:16:48PM +0100, Catalin Marinas wrote:quoted
Newer versions of gcc generate unaligned accesses by default, causing kernel panics when CONFIG_ALIGNMENT_TRAP is enabled. This patch adds the -mno-unaligned-access option to gcc.This description doesn't make sense. If we have alignment traps enabled, then we _expect_ to fix up unaligned loads and stores. Therefore there should be no panic if CONFIG_ALIGNMENT_TRAP is enabled. So what's the _actual_ problem that this is trying to address? What's the panic/oops look like? And that information should be in the commit description _anyway_.
OK, not clear from my commit log. See below for details (I'll add them to the log): http://www.codesourcery.com/archives/arm-gnu/msg04202.html Basically the fault happens before we call alignment_init(). There are other ways to fix this issue (like initialising the alignment handler earlier). -- Catalin