Re: [Xen-devel] printk from softirq on xen: hard lockup
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: 2015-08-04 23:01:34
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Hey David, Sorry for the premature response on my phone earlier. Real reply follows.
quoted
rcu_read_lock, when using Xen PV. Relevant excerpts of the^^ PV guest?
Yes. The lockup occurs on a PV guest. Nothing special at all about the configuration. Vanilla upstream 4.1.3 kernel.
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__xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56 56 while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY)^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ => HVM guest Which is it?
That's odd. It's a PV guest, not an HVM nor PVH guest.
A HVM guest's serial console may be particularly slow (since it's emulated by qemu). Try using the PV console?
I am using the PV console. But actually the problem occurs too even if /proc/sys/kernel/printk is set to all zeros (no klog on the console). The plot thickens?