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authorLinus Torvalds <torvalds@linux-foundation.org>2013-09-25 15:50:53 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-09-25 15:50:53 -0700
commit4b97280675f45c1650ee4e388bd711ecbb18c4b4 (patch)
tree45f9de3f355ac9245b9bda38e61204725cc7d991 /arch/x86/xen/spinlock.c
parente93dd910b906d2bb881f334685eb03431fd3fa48 (diff)
parent15a3eac0784edb73cb2ec0f0c97705ba4bd39b3f (diff)
Merge tag 'stable/for-linus-3.12-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull Xen fixes from Konrad Rzeszutek Wilk: "Bug-fixes and one update to the kernel-paramters.txt documentation. - Fix PV spinlocks triggering jump_label code bug - Remove extraneous code in the tpm front driver - Fix ballooning out of pages when non-preemptible - Fix deadlock when using a 32-bit initial domain with large amount of memory - Add xen_nopvpsin parameter to the documentation" * tag 'stable/for-linus-3.12-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/spinlock: Document the xen_nopvspin parameter. xen/p2m: check MFN is in range before using the m2p table xen/balloon: don't alloc page while non-preemptible xen: Do not enable spinlocks before jump_label_init() has executed tpm: xen-tpmfront: Remove the locality sysfs attribute tpm: xen-tpmfront: Fix default durations
Diffstat (limited to 'arch/x86/xen/spinlock.c')
-rw-r--r--arch/x86/xen/spinlock.c26
1 files changed, 24 insertions, 2 deletions
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 253f63fceea..be6b8607895 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -259,6 +259,14 @@ void xen_uninit_lock_cpu(int cpu)
}
+/*
+ * Our init of PV spinlocks is split in two init functions due to us
+ * using paravirt patching and jump labels patching and having to do
+ * all of this before SMP code is invoked.
+ *
+ * The paravirt patching needs to be done _before_ the alternative asm code
+ * is started, otherwise we would not patch the core kernel code.
+ */
void __init xen_init_spinlocks(void)
{
@@ -267,12 +275,26 @@ void __init xen_init_spinlocks(void)
return;
}
- static_key_slow_inc(&paravirt_ticketlocks_enabled);
-
pv_lock_ops.lock_spinning = PV_CALLEE_SAVE(xen_lock_spinning);
pv_lock_ops.unlock_kick = xen_unlock_kick;
}
+/*
+ * While the jump_label init code needs to happend _after_ the jump labels are
+ * enabled and before SMP is started. Hence we use pre-SMP initcall level
+ * init. We cannot do it in xen_init_spinlocks as that is done before
+ * jump labels are activated.
+ */
+static __init int xen_init_spinlocks_jump(void)
+{
+ if (!xen_pvspin)
+ return 0;
+
+ static_key_slow_inc(&paravirt_ticketlocks_enabled);
+ return 0;
+}
+early_initcall(xen_init_spinlocks_jump);
+
static __init int xen_parse_nopvspin(char *arg)
{
xen_pvspin = false;