3.4-stable patches

added patches:
	powerpc-kvm-fix-rare-but-potential-deadlock-scene.patch
	tty-pmac_zilog-check-existence-of-ports-in-pmz_console_init.patch

diff --git a/queue-3.4/powerpc-kvm-fix-rare-but-potential-deadlock-scene.patch b/queue-3.4/powerpc-kvm-fix-rare-but-potential-deadlock-scene.patch
new file mode 100644 (file)
index 0000000..56c2f34
--- /dev/null
+++ b/queue-3.4/powerpc-kvm-fix-rare-but-potential-deadlock-scene.patch
@@ -0,0 +1,77 @@
+From 91648ec09c1ef69c4d840ab6dab391bfb452d554 Mon Sep 17 00:00:00 2001
+From: pingfan liu <qemulist@gmail.com>
+Date: Fri, 15 Nov 2013 16:35:00 +0800
+Subject: powerpc: kvm: fix rare but potential deadlock scene
+
+From: pingfan liu <qemulist@gmail.com>
+
+commit 91648ec09c1ef69c4d840ab6dab391bfb452d554 upstream.
+
+Since kvmppc_hv_find_lock_hpte() is called from both virtmode and
+realmode, so it can trigger the deadlock.
+
+Suppose the following scene:
+
+Two physical cpuM, cpuN, two VM instances A, B, each VM has a group of
+vcpus.
+
+If on cpuM, vcpu_A_1 holds bitlock X (HPTE_V_HVLOCK), then is switched
+out, and on cpuN, vcpu_A_2 try to lock X in realmode, then cpuN will be
+caught in realmode for a long time.
+
+What makes things even worse if the following happens,
+  On cpuM, bitlockX is hold, on cpuN, Y is hold.
+  vcpu_B_2 try to lock Y on cpuM in realmode
+  vcpu_A_2 try to lock X on cpuN in realmode
+
+Oops! deadlock happens
+
+Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com>
+Reviewed-by: Paul Mackerras <paulus@samba.org>
+Signed-off-by: Alexander Graf <agraf@suse.de>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ arch/powerpc/kvm/book3s_64_mmu_hv.c |    6 +++++-
+ arch/powerpc/kvm/book3s_hv_rm_mmu.c |    4 ++++
+ 2 files changed, 9 insertions(+), 1 deletion(-)
+
+--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
++++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
+@@ -393,11 +393,14 @@ static int kvmppc_mmu_book3s_64_hv_xlate
+               slb_v = vcpu->kvm->arch.vrma_slb_v;
+       }
+ 
++      preempt_disable();
+       /* Find the HPTE in the hash table */
+       index = kvmppc_hv_find_lock_hpte(kvm, eaddr, slb_v,
+                                        HPTE_V_VALID | HPTE_V_ABSENT);
+-      if (index < 0)
++      if (index < 0) {
++              preempt_enable();
+               return -ENOENT;
++      }
+       hptep = (unsigned long *)(kvm->arch.hpt_virt + (index << 4));
+       v = hptep[0] & ~HPTE_V_HVLOCK;
+       gr = kvm->arch.revmap[index].guest_rpte;
+@@ -405,6 +408,7 @@ static int kvmppc_mmu_book3s_64_hv_xlate
+       /* Unlock the HPTE */
+       asm volatile("lwsync" : : : "memory");
+       hptep[0] = v;
++      preempt_enable();
+ 
+       gpte->eaddr = eaddr;
+       gpte->vpage = ((v & HPTE_V_AVPN) << 4) | ((eaddr >> 12) & 0xfff);
+--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
++++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+@@ -649,6 +649,10 @@ static int slb_base_page_shift[4] = {
+       20,     /* 1M, unsupported */
+ };
+ 
++/* When called from virtmode, this func should be protected by
++ * preempt_disable(), otherwise, the holding of HPTE_V_HVLOCK
++ * can trigger deadlock issue.
++ */
+ long kvmppc_hv_find_lock_hpte(struct kvm *kvm, gva_t eaddr, unsigned long slb_v,
+                             unsigned long valid)
+ {

diff --git a/queue-3.4/series b/queue-3.4/series
index b4f10addfccaa5d0d65946ef46bcd964bb09c600..1ef217b5bc293c2bac53032eef6e6e7cb587ad7a 100644 (file)
--- a/queue-3.4/series
+++ b/queue-3.4/series
@@ -1,3 +1,5 @@
 usb-serial-fix-race-in-generic-write.patch
 ceph-cleanup-aborted-requests-when-re-sending-requests.patch
 ceph-wake-up-safe-waiters-when-unregistering-request.patch
+powerpc-kvm-fix-rare-but-potential-deadlock-scene.patch
+tty-pmac_zilog-check-existence-of-ports-in-pmz_console_init.patch

diff --git a/queue-3.4/tty-pmac_zilog-check-existence-of-ports-in-pmz_console_init.patch b/queue-3.4/tty-pmac_zilog-check-existence-of-ports-in-pmz_console_init.patch
new file mode 100644 (file)
index 0000000..798cfbd
--- /dev/null
+++ b/queue-3.4/tty-pmac_zilog-check-existence-of-ports-in-pmz_console_init.patch
@@ -0,0 +1,47 @@
+From dc1dc2f8a5dd863bf2e79f338fc3ae29e99c683a Mon Sep 17 00:00:00 2001
+From: Geert Uytterhoeven <geert@linux-m68k.org>
+Date: Fri, 22 Nov 2013 16:47:26 +0100
+Subject: TTY: pmac_zilog, check existence of ports in pmz_console_init()
+
+From: Geert Uytterhoeven <geert@linux-m68k.org>
+
+commit dc1dc2f8a5dd863bf2e79f338fc3ae29e99c683a upstream.
+
+When booting a multi-platform m68k kernel on a non-Mac with "console=ttyS0"
+on the kernel command line, it crashes with:
+
+Unable to handle kernel NULL pointer dereference at virtual address   (null)
+Oops: 00000000
+PC: [<0013ad28>] __pmz_startup+0x32/0x2a0
+...
+Call Trace: [<002c5d3e>] pmz_console_setup+0x64/0xe4
+
+The normal tty driver doesn't crash, because init_pmz() checks
+pmz_ports_count again after calling pmz_probe().
+
+In the serial console initialization path, pmz_console_init() doesn't do
+this, causing the driver to crash later.
+
+Add a check for pmz_ports_count to fix this.
+
+Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
+Cc: Finn Thain <fthain@telegraphics.com.au>
+Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/tty/serial/pmac_zilog.c |    3 +++
+ 1 file changed, 3 insertions(+)
+
+--- a/drivers/tty/serial/pmac_zilog.c
++++ b/drivers/tty/serial/pmac_zilog.c
+@@ -2051,6 +2051,9 @@ static int __init pmz_console_init(void)
+       /* Probe ports */
+       pmz_probe();
+ 
++      if (pmz_ports_count == 0)
++              return -ENODEV;
++
+       /* TODO: Autoprobe console based on OF */
+       /* pmz_console.index = i; */
+       register_console(&pmz_console);