Running interrupt handlers with interrupts enabled can cause stack overflows. That has been observed with multiqueue NICs delivering all their interrupts to a single core. We might band aid that somehow by checking the interrupt stacks, but the real safe fix is to run the irq handlers with interrupts disabled. Drivers for whacky hardware still can reenable them in the handler itself, if the need arises. (They do already due to lockdep) The risk of doing this is rather low: - lockdep already enforces this - CONFIG_NOHZ has shaken out the drivers which relied on jiffies updates - time keeping is not longer sensitive to the timer interrupt being delayed Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Miller <davem@davemloft.net> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Linus Torvalds <torvalds@osdl.org> LKML-Reference: <20100326000405.758579387@linutronix.de>
Use radix_tree irq_desc_tree instead of irq_desc_ptrs.
-v2: according to Eric and cyrill to use radix_tree_lookup_slot and
radix_tree_replace_slot
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-32-git-send-email-yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Add replace_irq_desc() instead of poking at the array directly. -v2: remove unneeded boundary check in replace_irq_desc Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <1265793639-15071-31-git-send-email-yinghai@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
mem_init is moved early already. Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <1265793639-15071-29-git-send-email-yinghai@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Convert locks which cannot be sleeping locks in preempt-rt to raw_spinlocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@elte.hu>
After m68k's task_thread_info() doesn't refer to current, it's possible to remove sched.h from interrupt.h and not break m68k! Many thanks to Heiko Carstens for allowing this. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
when there is no ram on node 0. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> LKML-Reference: <4A95C32D.5040605@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo had [ 0.000000] ------------[ cut here ]------------ [ 0.000000] WARNING: at mm/bootmem.c:537 alloc_arch_preferred_bootmem+0x2b/0x71() [ 0.000000] Hardware name: System Product Name [ 0.000000] Modules linked in: [ 0.000000] Pid: 0, comm: swapper Tainted: G W 2.6.30-tip-03087-g0bb2618-dirty #52506 [ 0.000000] Call Trace: [ 0.000000] [<81032588>] warn_slowpath_common+0x60/0x90 [ 0.000000] [<810325c5>] warn_slowpath_null+0xd/0x10 [ 0.000000] [<819d1bc0>] alloc_arch_preferred_bootmem+0x2b/0x71 [ 0.000000] [<819d1c31>] ___alloc_bootmem_nopanic+0x2b/0x9a [ 0.000000] [<81050a0a>] ? lock_release+0xac/0xb2 [ 0.000000] [<819d1d4c>] ___alloc_bootmem+0xe/0x2d [ 0.000000] [<819d1e9f>] __alloc_bootmem+0xa/0xc [ 0.000000] [<819d7c63>] alloc_bootmem_cpumask_var+0x21/0x26 [ 0.000000] [<819d0cc8>] early_irq_init+0x15/0x10d [ 0.000000] [<819bb75a>] start_kernel+0x167/0x326 [ 0.000000] [<819bb06b>] __init_begin+0x6b/0x70 [ 0.000000] ---[ end trace 4eaa2a86a8e2da23 ]--- [ 0.000000] NR_IRQS:2304 nr_irqs:424 [ 0.000000] CPU 0 irqstacks, hard=821e6000 soft=821e7000 we need to update init_irq_default_affinity Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Fixes the following problem: [ 0.000000] Experimental hierarchical RCU init done. [ 0.000000] NR_IRQS:4352 nr_irqs:256 [ 0.000000] ------------[ cut here ]------------ [ 0.000000] WARNING: at mm/bootmem.c:537 alloc_arch_preferred_bootmem+0x40/0x7e() [ 0.000000] Hardware name: To Be Filled By O.E.M. [ 0.000000] Pid: 0, comm: swapper Not tainted 2.6.30-tip-02161-g7a74539-dirty #59709 [ 0.000000] Call Trace: [ 0.000000] [<ffffffff823f8c8e>] ? alloc_arch_preferred_bootmem+0x40/0x7e [ 0.000000] [<ffffffff81067168>] warn_slowpath_common+0x88/0xcb [ 0.000000] [<ffffffff810671d2>] warn_slowpath_null+0x27/0x3d [ 0.000000] [<ffffffff823f8c8e>] alloc_arch_preferred_bootmem+0x40/0x7e [ 0.000000] [<ffffffff823f9307>] ___alloc_bootmem_nopanic+0x4e/0xec [ 0.000000] [<ffffffff823f93c5>] ___alloc_bootmem+0x20/0x61 [ 0.000000] [<ffffffff823f962e>] __alloc_bootmem+0x1e/0x34 [ 0.000000] [<ffffffff823f757c>] early_irq_init+0x6d/0x118 [ 0.000000] [<ffffffff823e0140>] ? early_idt_handler+0x0/0x71 [ 0.000000] [<ffffffff823e0cf7>] start_kernel+0x192/0x394 [ 0.000000] [<ffffffff823e0140>] ? early_idt_handler+0x0/0x71 [ 0.000000] [<ffffffff823e02ad>] x86_64_start_reservations+0xb4/0xcf [ 0.000000] [<ffffffff823e0000>] ? __init_begin+0x0/0x140 [ 0.000000] [<ffffffff823e0420>] x86_64_start_kernel+0x158/0x17b [ 0.000000] ---[ end trace a7919e7f17c0a725 ]--- [ 0.000000] Fast TSC calibration using PIT [ 0.000000] Detected 2002.510 MHz processor. [ 0.004000] Console: colour VGA+ 80x25 Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Don't hardcode to node zero for early boot IRQ setup memory allocations. [ penberg@cs.helsinki.fi: minor cleanups ] Cc: Ingo Molnar <mingo@elte.hu> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>