From: Zhang Yanfei <zhangyanfei.yes@gmail.com>
To: Marcelo Tosatti <mtosatti@redhat.com>,
Gleb Natapov <gleb@redhat.com>,
"Eric W. Biederman" <ebiederm@xmission.com>
Cc: kexec@lists.infradead.org,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
linux-kernel@vger.kernel.org
Subject: [PATCH v11 1/2] x86/kexec: VMCLEAR VMCSs loaded on all cpus if necessary
Date: Thu, 06 Dec 2012 23:40:47 +0800 [thread overview]
Message-ID: <50C0BC7F.8030302@gmail.com> (raw)
In-Reply-To: <50C0BB90.1080804@gmail.com>
From: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
This patch provides a way to VMCLEAR VMCSs related to guests
on all cpus before executing the VMXOFF when doing kdump. This
is used to ensure the VMCSs in the vmcore updated and
non-corrupted.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
---
arch/x86/include/asm/kexec.h | 2 ++
arch/x86/kernel/crash.c | 32 ++++++++++++++++++++++++++++++++
2 files changed, 34 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
index 317ff17..28feeba 100644
--- a/arch/x86/include/asm/kexec.h
+++ b/arch/x86/include/asm/kexec.h
@@ -163,6 +163,8 @@ struct kimage_arch {
};
#endif
+extern void (*crash_vmclear_loaded_vmcss)(void);
+
#endif /* __ASSEMBLY__ */
#endif /* _ASM_X86_KEXEC_H */
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index 13ad899..b914b7f 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -16,6 +16,7 @@
#include <linux/delay.h>
#include <linux/elf.h>
#include <linux/elfcore.h>
+#include <linux/module.h>
#include <asm/processor.h>
#include <asm/hardirq.h>
@@ -30,6 +31,27 @@
int in_crash_kexec;
+/*
+ * This is used to VMCLEAR all VMCSs loaded on the
+ * processor. And when loading kvm_intel module, the
+ * callback function pointer will be assigned.
+ *
+ * protected by rcu.
+ */
+void (*crash_vmclear_loaded_vmcss)(void) = NULL;
+EXPORT_SYMBOL_GPL(crash_vmclear_loaded_vmcss);
+
+static inline void cpu_crash_vmclear_loaded_vmcss(void)
+{
+ void (*do_vmclear_operation)(void) = NULL;
+
+ rcu_read_lock();
+ do_vmclear_operation = rcu_dereference(crash_vmclear_loaded_vmcss);
+ if (do_vmclear_operation)
+ do_vmclear_operation();
+ rcu_read_unlock();
+}
+
#if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
static void kdump_nmi_callback(int cpu, struct pt_regs *regs)
@@ -46,6 +68,11 @@ static void kdump_nmi_callback(int cpu, struct pt_regs *regs)
#endif
crash_save_cpu(regs, cpu);
+ /*
+ * VMCLEAR VMCSs loaded on all cpus if needed.
+ */
+ cpu_crash_vmclear_loaded_vmcss();
+
/* Disable VMX or SVM if needed.
*
* We need to disable virtualization on all CPUs.
@@ -88,6 +115,11 @@ void native_machine_crash_shutdown(struct pt_regs *regs)
kdump_nmi_shootdown_cpus();
+ /*
+ * VMCLEAR VMCSs loaded on this cpu if needed.
+ */
+ cpu_crash_vmclear_loaded_vmcss();
+
/* Booting kdump kernel with VMX or SVM enabled won't work,
* because (among other limitations) we can't disable paging
* with the virt flags.
--
1.7.1
next prev parent reply other threads:[~2012-12-06 15:40 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-06 15:36 [PATCH v11 0/2] x86: vmclear vmcss on all cpus when doing kdump if necessary Zhang Yanfei
2012-12-06 15:40 ` Zhang Yanfei [this message]
2012-12-06 15:43 ` [PATCH v11 2/2] KVM-INTEL: provide the vmclear function and a bitmap to support VMCLEAR in kdump Zhang Yanfei
2012-12-06 16:28 ` [PATCH v11 0/2] x86: vmclear vmcss on all cpus when doing kdump if necessary Gleb Natapov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=50C0BC7F.8030302@gmail.com \
--to=zhangyanfei.yes@gmail.com \
--cc=ebiederm@xmission.com \
--cc=gleb@redhat.com \
--cc=kexec@lists.infradead.org \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mtosatti@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).