Re: [PATCH urgent] MIPS: fix micro-assembly overflow in set_except_vector

[Florian Fainelli <florian@openwrt.org>]

Hi Thomas,

On Monday 01 February 2010 11:36:28 Thomas Bogendoerfer wrote:
> On Mon, Feb 01, 2010 at 10:27:37AM +0100, Florian Fainelli wrote:
> > Commit 24a6d9866c5f15ba7e5b14dc17be4b6edba21d0e broke
> > the installation of handlers for boards which have their
> > handlers above a 1 << 26 address. Fix this by making sure that
> > jump_mask does not excess 0xfc000000 and add the missing ~ operator
> 
> j can handle 28 bit jump targets (26 bit in instruction plus two 0 bits
> for 32bit aligment), so 0xf000000 was IMHO fine.

Corrected version below, thanks.
---
From: Florian Fainelli <florian@openwrt.org>
Subject: [PATCH urgent] MIPS: fix micro-assembly overflow in set_except_vector

Commit 24a6d9866c5f15ba7e5b14dc17be4b6edba21d0e broke
the installation of handlers for boards which have their
handlers above 0xf0000000. Fix this by adding the missing
~ operator to jump_mask when loading the handler target
address into buf.

Reported-by: Maxime Bizon <mbizon@freebox.fr>
Acked-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Florian Fainelli <florian@openwrt.org>
---
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 7693929..af176b8 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -1283,7 +1283,7 @@ void __init *set_except_vector(int n, void *addr)
 		u32 *buf = (u32 *)(ebase + 0x200);
 		unsigned int k0 = 26;
 		if ((handler & jump_mask) == ((ebase + 0x200) & jump_mask)) {
-			uasm_i_j(&buf, handler & jump_mask);
+			uasm_i_j(&buf, handler & ~jump_mask);
 			uasm_i_nop(&buf);
 		} else {
 			UASM_i_LA(&buf, k0, handler);