Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1258166

[PATCH 3.12 032/123] x86/xen: Support kexec/kdump in HVM guests by doing a soft reset

From Jiri Slaby <jslaby@suse.cz>
Newsgroups linux.kernel
Subject [PATCH 3.12 032/123] x86/xen: Support kexec/kdump in HVM guests by doing a soft reset
Date 2015-10-28 15:30 +0100
Message-ID <qozTJ-3KE-45@gated-at.bofh.it> (permalink)
References <qozqF-3k6-9@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw

From: Vitaly Kuznetsov <vkuznets@redhat.com>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

commit 0b34a166f291d255755be46e43ed5497cdd194f2 upstream.

Currently there is a number of issues preventing PVHVM Xen guests from
doing successful kexec/kdump:

  - Bound event channels.
  - Registered vcpu_info.
  - PIRQ/emuirq mappings.
  - shared_info frame after XENMAPSPACE_shared_info operation.
  - Active grant mappings.

Basically, newly booted kernel stumbles upon already set up Xen
interfaces and there is no way to reestablish them. In Xen-4.7 a new
feature called 'soft reset' is coming. A guest performing kexec/kdump
operation is supposed to call SCHEDOP_shutdown hypercall with
SHUTDOWN_soft_reset reason before jumping to new kernel. Hypervisor
(with some help from toolstack) will do full domain cleanup (but
keeping its memory and vCPU contexts intact) returning the guest to
the state it had when it was first booted and thus allowing it to
start over.

Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is
probably OK as by default all unknown shutdown reasons cause domain
destroy with a message in toolstack log: 'Unknown shutdown reason code
5. Destroying domain.'  which gives a clue to what the problem is and
eliminates false expectations.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 arch/x86/xen/enlighten.c      | 23 +++++++++++++++++++++++
 include/xen/interface/sched.h |  8 ++++++++
 2 files changed, 31 insertions(+)

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 2cbc2f2cf43e..aa82317de9c0 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -33,6 +33,10 @@
 #include <linux/memblock.h>
 #include <linux/edd.h>
 
+#ifdef CONFIG_KEXEC_CORE
+#include <linux/kexec.h>
+#endif
+
 #include <xen/xen.h>
 #include <xen/events.h>
 #include <xen/interface/xen.h>
@@ -1746,6 +1750,21 @@ static struct notifier_block xen_hvm_cpu_notifier = {
 	.notifier_call	= xen_hvm_cpu_notify,
 };
 
+#ifdef CONFIG_KEXEC_CORE
+static void xen_hvm_shutdown(void)
+{
+	native_machine_shutdown();
+	if (kexec_in_progress)
+		xen_reboot(SHUTDOWN_soft_reset);
+}
+
+static void xen_hvm_crash_shutdown(struct pt_regs *regs)
+{
+	native_machine_crash_shutdown(regs);
+	xen_reboot(SHUTDOWN_soft_reset);
+}
+#endif
+
 static void __init xen_hvm_guest_init(void)
 {
 	init_hvm_pv_info();
@@ -1762,6 +1781,10 @@ static void __init xen_hvm_guest_init(void)
 	x86_init.irqs.intr_init = xen_init_IRQ;
 	xen_hvm_init_time_ops();
 	xen_hvm_init_mmu_ops();
+#ifdef CONFIG_KEXEC_CORE
+	machine_ops.shutdown = xen_hvm_shutdown;
+	machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
+#endif
 }
 
 static uint32_t __init xen_hvm_platform(void)
diff --git a/include/xen/interface/sched.h b/include/xen/interface/sched.h
index 9ce083960a25..f18490985fc8 100644
--- a/include/xen/interface/sched.h
+++ b/include/xen/interface/sched.h
@@ -107,5 +107,13 @@ struct sched_watchdog {
 #define SHUTDOWN_suspend    2  /* Clean up, save suspend info, kill.         */
 #define SHUTDOWN_crash      3  /* Tell controller we've crashed.             */
 #define SHUTDOWN_watchdog   4  /* Restart because watchdog time expired.     */
+/*
+ * Domain asked to perform 'soft reset' for it. The expected behavior is to
+ * reset internal Xen state for the domain returning it to the point where it
+ * was created but leaving the domain's memory contents and vCPU contexts
+ * intact. This will allow the domain to start over and set up all Xen specific
+ * interfaces again.
+ */
+#define SHUTDOWN_soft_reset 5
 
 #endif /* __XEN_PUBLIC_SCHED_H__ */
-- 
2.6.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 3.12 001/123] x86/nmi/64: Fix a paravirt stack-clobbering bug in the NMI code Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:00 +0100
  [PATCH 3.12 027/123] ARM: dts: omap5-uevm.dts: fix i2c5 pinctrl offsets Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:00 +0100
  [PATCH 3.12 035/123] arc,hexagon: Delete asm/barrier.h Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:00 +0100
  [PATCH 3.12 037/123] spi: Fix documentation of spi_alloc_master() Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:00 +0100
  [PATCH 3.12 029/123] x86/apic: Serialize LVTT and TSC_DEADLINE writes Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:00 +0100
  [PATCH 3.12 026/123] windfarm: decrement client count when unregistering Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:00 +0100
  [PATCH 3.12 021/123] perf stat: Get correct cpu id for print_aggr Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:30 +0100
  [PATCH 3.12 030/123] x86/platform: Fix Geode LX timekeeping in the generic x86 build Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:30 +0100
  [PATCH 3.12 031/123] x86/mm: Set NX on gap between __ex_table and rodata Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:30 +0100
  [PATCH 3.12 033/123] arch: Clean up asm/barrier.h implementations using asm-generic/barrier.h Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:30 +0100
  [PATCH 3.12 032/123] x86/xen: Support kexec/kdump in HVM guests by doing a soft reset Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:30 +0100
    Re: [PATCH 3.12 032/123] x86/xen: Support kexec/kdump in HVM guests  by doing a soft reset Luis Henriques <luis.henriques@canonical.com> - 2015-10-28 16:30 +0100
      Re: [PATCH 3.12 032/123] x86/xen: Support kexec/kdump in HVM guests  by doing a soft reset Jiri Slaby <jslaby@suse.cz> - 2015-10-28 16:40 +0100
  [PATCH 3.12 022/123] perf header: Fixup reading of HEADER_NRCPUS feature Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:30 +0100
  [PATCH 3.12 034/123] arch: Move smp_mb__{before,after}_atomic_{inc,dec}.h into asm/atomic.h Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:30 +0100
  [PATCH 3.12 025/123] ARM: 8429/1: disable GCC SRA optimization Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:30 +0100
  [PATCH 3.12 028/123] dmaengine: dw: properly read DWC_PARAMS register Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:30 +0100
  [PATCH 3.12 014/123] ARM: 7880/1: Clear the IT state independent of the Thumb-2 mode Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 036/123] sched/core: Fix TASK_DEAD race in finish_task_switch() Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 012/123] s390/3270: redraw screen on unsolicited device end Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 013/123] Use WARN_ON_ONCE for missing X86_FEATURE_NRIPS Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 023/123] hwmon: (nct6775) Swap STEP_UP_TIME and STEP_DOWN_TIME registers for most chips Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 017/123] kvm: fix zero length mmio searching Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 018/123] scsi: fix scsi_error_handler vs. scsi_host_dev_release race Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 002/123] x86/paravirt: Replace the paravirt nop with a bona fide empty function Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 020/123] perf hists: Update the column width for the "srcline" sort key Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 019/123] iser-target: remove command with state ISTATE_REMOVE Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 024/123] ARM: fix Thumb2 signal handling when ARMv6 is enabled Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 016/123] ALSA: hda - Control SPDIF out pin on MacBookPro 11,2 Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 015/123] net: add length argument to skb_copy_and_csum_datagram_iovec Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:40 +0100
  [PATCH 3.12 004/123] rcu: Reject memory-order-induced stall-warning false positives Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:50 +0100
  [PATCH 3.12 005/123] sched: Fix cpu_active_mask/cpu_online_mask race Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:50 +0100
  [PATCH 3.12 007/123] xhci: rework cycle bit checking for new dequeue pointers Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:50 +0100
  [PATCH 3.12 006/123] xhci: Workaround for PME stuck issues in Intel xhci Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:50 +0100
  [PATCH 3.12 009/123] USB: usbtmc: add device quirk for Rigol DS6104 Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:50 +0100
    Re: [PATCH 3.12 009/123] USB: usbtmc: add device quirk for Rigol DS6104 Teunis van Beelen <teuniz@gmail.com> - 2015-10-28 16:40 +0100
  [PATCH 3.12 008/123] usb: core: Fix USB 3.0 devices lost in NOTATTACHED state after a hub port reset Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:50 +0100
  [PATCH 3.12 010/123] client MUST ignore EncryptionKeyLength if CAP_EXTENDED_SECURITY is set Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:50 +0100
  [PATCH 3.12 011/123] iommu/amd: Handle integer overflow in dma_ops_area_alloc Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:50 +0100
  [PATCH 3.12 003/123] jbd2: avoid infinite loop when destroying aborted journal Jiri Slaby <jslaby@suse.cz> - 2015-10-28 15:50 +0100

csiph-web