From ae4f073c40bf677b03826262e6022b4a251fe437 Mon Sep 17 00:00:00 2001 From: Robin Getz Date: Mon, 22 Jun 2009 02:02:16 +0000 Subject: Blackfin: make EVT3->EVT5 lowering more robust wrt IPEND[4] We handle many exceptions at EVT5 (hardware error level) so that we can catch exceptions in our exception handling code. Today - if the global interrupt enable bit (IPEND[4]) is set (interrupts disabled) our trap handling code goes into a infinite loop, since we need interrupts to be on to defer things to EVT5. Normal kernel code should not trigger this for any reason as IPEND[4] gets cleared early (when doing an interrupt context save) and the kernel stack there should be sane (or something much worse is happening in the system). But there have been a few times where this has happened, so this change makes sure we dump a proper crash message even when things have gone south. Signed-off-by: Robin Getz Signed-off-by: Mike Frysinger --- arch/blackfin/kernel/asm-offsets.c | 1 + arch/blackfin/kernel/traps.c | 19 ++++++++++--------- 2 files changed, 11 insertions(+), 9 deletions(-) (limited to 'arch/blackfin/kernel') diff --git a/arch/blackfin/kernel/asm-offsets.c b/arch/blackfin/kernel/asm-offsets.c index b5df9459d6d5..8ad4f2c69961 100644 --- a/arch/blackfin/kernel/asm-offsets.c +++ b/arch/blackfin/kernel/asm-offsets.c @@ -145,6 +145,7 @@ int main(void) DEFINE(PDA_EXBUF, offsetof(struct blackfin_pda, ex_buf)); DEFINE(PDA_EXIMASK, offsetof(struct blackfin_pda, ex_imask)); DEFINE(PDA_EXSTACK, offsetof(struct blackfin_pda, ex_stack)); + DEFINE(PDA_EXIPEND, offsetof(struct blackfin_pda, ex_ipend)); #ifdef ANOMALY_05000261 DEFINE(PDA_LFRETX, offsetof(struct blackfin_pda, last_cplb_fault_retx)); #endif diff --git a/arch/blackfin/kernel/traps.c b/arch/blackfin/kernel/traps.c index bf2b2d1f8ae5..fccf741ed3b5 100644 --- a/arch/blackfin/kernel/traps.c +++ b/arch/blackfin/kernel/traps.c @@ -267,11 +267,6 @@ asmlinkage void trap_c(struct pt_regs *fp) * double faults if the stack has become corrupt */ -#ifndef CONFIG_KGDB - /* IPEND is skipped if KGDB isn't enabled (see entry code) */ - fp->ipend = bfin_read_IPEND(); -#endif - /* trap_c() will be called for exceptions. During exceptions * processing, the pc value should be set with retx value. * With this change we can cleanup some code in signal.c- TODO @@ -1116,10 +1111,16 @@ void show_regs(struct pt_regs *fp) verbose_printk(KERN_NOTICE "%s", linux_banner); - verbose_printk(KERN_NOTICE "\nSEQUENCER STATUS:\t\t%s\n", - print_tainted()); - verbose_printk(KERN_NOTICE " SEQSTAT: %08lx IPEND: %04lx SYSCFG: %04lx\n", - (long)fp->seqstat, fp->ipend, fp->syscfg); + verbose_printk(KERN_NOTICE "\nSEQUENCER STATUS:\t\t%s\n", print_tainted()); + verbose_printk(KERN_NOTICE " SEQSTAT: %08lx IPEND: %04lx IMASK: %04lx SYSCFG: %04lx\n", + (long)fp->seqstat, fp->ipend, cpu_pda[smp_processor_id()].ex_imask, fp->syscfg); + if (fp->ipend & EVT_IRPTEN) + verbose_printk(KERN_NOTICE " Global Interrupts Disabled (IPEND[4])\n"); + if (!(cpu_pda[smp_processor_id()].ex_imask & (EVT_IVG13 | EVT_IVG12 | EVT_IVG11 | + EVT_IVG10 | EVT_IVG9 | EVT_IVG8 | EVT_IVG7 | EVT_IVTMR))) + verbose_printk(KERN_NOTICE " Peripheral interrupts masked off\n"); + if (!(cpu_pda[smp_processor_id()].ex_imask & (EVT_IVG15 | EVT_IVG14))) + verbose_printk(KERN_NOTICE " Kernel interrupts masked off\n"); if ((fp->seqstat & SEQSTAT_EXCAUSE) == VEC_HWERR) { verbose_printk(KERN_NOTICE " HWERRCAUSE: 0x%lx\n", (fp->seqstat & SEQSTAT_HWERRCAUSE) >> 14); -- cgit v1.2.3