Doug / smarc-fsl-linux-kernel

Download as
Browse Code ยป

Commit e20800fd5cec2a75639a32e956b1cdc023cb87ce

Authored by Will Deacon
Committed by Linus Torvalds
1 parent cd8d233175
Exists in smarc-l5.0.0_1.0.0-ga and in 5 other branches imx_3.10.17_1.0.1_ga, imx_3.10.53_1.1.0_ga, imx_3.14.28_1.0.0_ga, smarc-imx_3.10.53_1.1.0_ga, smarc-imx_3.14.28_1.0.0_ga

alpha: irq: run all handlers with interrupts disabled 

Linux has expected that interrupt handlers are executed with local
interrupts disabled for a while now, so ensure that this is the case on
Alpha even for non-device interrupts such as IPIs.

Without this patch, secondary boot results in the following backtrace:

  warning: at kernel/softirq.c:139 __local_bh_enable+0xb8/0xd0()
  trace:
    __local_bh_enable+0xb8/0xd0
    irq_enter+0x74/0xa0
    scheduler_ipi+0x50/0x100
    handle_ipi+0x84/0x260
    do_entint+0x1ac/0x2e0
    irq_exit+0x60/0xa0
    handle_irq+0x98/0x100
    do_entint+0x2c8/0x2e0
    ret_from_sys_call+0x0/0x10
    load_balance+0x3e4/0x870
    cpu_idle+0x24/0x80
    rcu_eqs_enter_common.isra.38+0x0/0x120
    cpu_idle+0x40/0x80
    rest_init+0xc0/0xe0
    _stext+0x1c/0x20

A similar dump occurs if you try to reboot using magic-sysrq.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Michael Cree <mcree@orcon.net.nz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Showing 2 changed files with 8 additions and 8 deletions Side-by-side Diff

arch/alpha/kernel/irq.c
Diff comments   View file @ e20800f
... ... @@ -117,13 +117,6 @@
117 117 return;
118 118 }
119 119  
120   - /*
121   - * From here we must proceed with IPL_MAX. Note that we do not
122   - * explicitly enable interrupts afterwards - some MILO PALcode
123   - * (namely LX164 one) seems to have severe problems with RTI
124   - * at IPL 0.
125   - */
126   - local_irq_disable();
127 120 irq_enter();
128 121 generic_handle_irq_desc(irq, desc);
129 122 irq_exit();
arch/alpha/kernel/irq_alpha.c
Diff comments   View file @ e20800f
... ... @@ -45,6 +45,14 @@
45 45 unsigned long la_ptr, struct pt_regs *regs)
46 46 {
47 47 struct pt_regs *old_regs;
  48 +
  49 + /*
  50 + * Disable interrupts during IRQ handling.
  51 + * Note that there is no matching local_irq_enable() due to
  52 + * severe problems with RTI at IPL0 and some MILO PALcode
  53 + * (namely LX164).
  54 + */
  55 + local_irq_disable();
48 56 switch (type) {
49 57 case 0:
50 58 #ifdef CONFIG_SMP
... ... @@ -62,7 +70,6 @@
62 70 {
63 71 long cpu;
64 72  
65   - local_irq_disable();
66 73 smp_percpu_timer_interrupt(regs);
67 74 cpu = smp_processor_id();
68 75 if (cpu != boot_cpuid) {