From: Bernd Schmidt Date: Wed, 23 Apr 2008 18:56:36 +0000 (+0800) Subject: [Blackfin] arch: fix bug - a crash on bootup with CONFIG_MPU on the BF548 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d56daae9bec92ae4b0c115db787a0fcc4c17b381;p=linux-2.6 [Blackfin] arch: fix bug - a crash on bootup with CONFIG_MPU on the BF548 The function flush_switched_dcplbs was clearing the CPLB entries covering the process permission bitmasks. This means that the sequence flush_switched_dcplbs (); set_mask_dcplbs(mm->context.page_rwx_mask); has a problem: if kernel code (such as an interrupt) causes a CPLB miss before set_mask_dcplbs completes, the CPLB handler function causes a double fault, with an instantaneous reboot. This bug fix is dedicated to Michael Hennerich, the only person in the world capable of providing working JTAG hardware. Signed-off-by: Bernd Schmidt Signed-off-by: Bryan Wu --- diff --git a/arch/blackfin/kernel/cplb-mpu/cplbmgr.c b/arch/blackfin/kernel/cplb-mpu/cplbmgr.c index 6f1c053903..f23bba5c6e 100644 --- a/arch/blackfin/kernel/cplb-mpu/cplbmgr.c +++ b/arch/blackfin/kernel/cplb-mpu/cplbmgr.c @@ -307,7 +307,7 @@ void flush_switched_cplbs(void) enable_icplb(); disable_dcplb(); - for (i = first_mask_dcplb; i < MAX_CPLBS; i++) { + for (i = first_switched_dcplb; i < MAX_CPLBS; i++) { dcplb_tbl[i].data = 0; bfin_write32(DCPLB_DATA0 + i * 4, 0); }