linux-stable.git/arch/powerpc, branch v3.8 Linux kernel stable tree powerpc/mm: Fix hash computation function 2013-02-04T04:15:08+00:00 Aneesh Kumar K.V aneesh.kumar@linux.vnet.ibm.com 2013-01-29T19:40:42+00:00 eda8eebdd153c48a4e2a3a3ac3cd9e2e31f5c6b3 The ASM version of hash computation function was truncating the upper bit. Make the ASM version similar to hpt_hash function. Remove masking vsid bits. Without this patch, we observed hang during bootup due to not satisfying page fault request correctly. The fault handler used wrong hash values to update the HPTE. Hence we kept looping with page fault. hash_page(ea=000001003e260008, access=203, trap=300 ip=3fff91787134 dsisr 42000000 The computed value of hash 000000000f22f390 update: avpnv=4003e46054003e00, hash=000000000722f390, f=80000006, psize: 2 ... BenH: The over-masking has been there for ever but only hurts with the new 64T support introduced in 3.7 Reported-by: Mike Qiu <qiudayu@linux.vnet.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Tested-by: Mike Qiu <qiudayu@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: <stable@vger.kernel.org> [v3.7] 
The ASM version of hash computation function was truncating the upper bit.
Make the ASM version similar to hpt_hash function. Remove masking vsid bits.
Without this patch, we observed hang during bootup due to not satisfying page
fault request correctly. The fault handler used wrong hash values to update
the HPTE. Hence we kept looping with page fault.

hash_page(ea=000001003e260008, access=203, trap=300 ip=3fff91787134 dsisr 42000000
The computed value of hash 000000000f22f390
update: avpnv=4003e46054003e00, hash=000000000722f390, f=80000006, psize: 2 ...

BenH: The over-masking has been there for ever but only hurts with the
new 64T support introduced in 3.7

Reported-by: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org> [v3.7]
powerpc: Max next_tb to prevent from replaying timer interrupt 2013-01-28T23:18:16+00:00 Tiejun Chen tiejun.chen@windriver.com 2013-01-15T17:01:19+00:00 689dfa894c57842a05bf6dc9f97e6bb71ec5f386 With lazy interrupt, we always call __check_irq_replaysome with decrementers_next_tb to check if we need to replay timer interrupt. So in hotplug case we also need to set decrementers_next_tb as MAX to make sure __check_irq_replay don't replay timer interrupt when return as we expect, otherwise we'll trap here infinitely. Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> 
With lazy interrupt, we always call __check_irq_replaysome with
decrementers_next_tb to check if we need to replay timer interrupt.
So in hotplug case we also need to set decrementers_next_tb as MAX
to make sure __check_irq_replay don't replay timer interrupt
when return as we expect, otherwise we'll trap here infinitely.

Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc: kernel/kgdb.c: Fix memory leakage 2013-01-28T23:18:15+00:00 Cong Ding dinggnu@gmail.com 2013-01-14T07:26:32+00:00 fefd9e6f8860249b2c284d89cb2e51fa71a9503a the variable backup_current_thread_info isn't freed before existing the function. Signed-off-by: Cong Ding <dinggnu@gmail.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> 
the variable backup_current_thread_info isn't freed before existing the
function.

Signed-off-by: Cong Ding <dinggnu@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/book3e: Disable interrupt after preempt_schedule_irq 2013-01-28T23:18:15+00:00 Tiejun Chen tiejun.chen@windriver.com 2013-01-06T00:49:34+00:00 572177d7c77db1981ba2563e01478126482c43bc In preempt case current arch_local_irq_restore() from preempt_schedule_irq() may enable hard interrupt but we really should disable interrupts when we return from the interrupt, and so that we don't get interrupted after loading SRR0/1. Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com> CC: <stable@vger.kernel.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> 
In preempt case current arch_local_irq_restore() from
preempt_schedule_irq() may enable hard interrupt but we really
should disable interrupts when we return from the interrupt,
and so that we don't get interrupted after loading SRR0/1.

Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/oprofile: Fix error in oprofile power7_marked_instr_event() function 2013-01-28T23:18:14+00:00 Carl E. Love cel@linux.vnet.ibm.com 2012-11-29T06:42:03+00:00 46ed7a76ae7770cb8ba733ee2b06273397ad8b5b The calculation for the left shift of the mask OPROFILE_PM_PMCSEL_MSK has an error. The calculation is should be to shift left by (max_cntrs - cntr) times the width of the pmsel field width. However, the #define OPROFILE_MAX_PMC_NUM was used instead of OPROFILE_PMSEL_FIELD_WIDTH. This patch fixes the calculation. Signed-off-by: Carl Love <cel@us.ibm.com> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> 
The calculation for the left shift of the mask OPROFILE_PM_PMCSEL_MSK has an
error.  The calculation is should be to shift left by (max_cntrs - cntr) times
the width of the pmsel field width.  However, the #define OPROFILE_MAX_PMC_NUM
was used instead of OPROFILE_PMSEL_FIELD_WIDTH.  This patch fixes the
calculation.

Signed-off-by: Carl Love <cel@us.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/pasemi: Fix crash on reboot 2013-01-28T23:18:14+00:00 Steven Rostedt rostedt@goodmis.org 2013-01-21T17:23:26+00:00 72640d880350165c3a7b8f2e4fb4bf852ea7b606 commit f96972f2dc "kernel/sys.c: call disable_nonboot_cpus() in kernel_restart()" added a call to disable_nonboot_cpus() on kernel_restart(), which tries to shutdown all the CPUs except the first one. The issue with the PA Semi, is that it does not support CPU hotplug. When the call is made to __cpu_down(), it calls the notifiers CPU_DOWN_PREPARE, and then tries to take the CPU down. One of the notifiers to the CPU hotplug code, is the cpufreq. The DOWN_PREPARE will call __cpufreq_remove_dev() which calls cpufreq_driver->exit. The PA Semi exit handler unmaps regions of I/O that is used by an interrupt that goes off constantly (system_reset_common, but it goes off during normal system operations too). I'm not sure exactly what this interrupt does. Running a simple function trace, you can see it goes off quite a bit: # tracer: function # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | <idle>-0 [001] 1558.859363: .pasemi_system_reset_exception <-.system_reset_exception <idle>-0 [000] 1558.860112: .pasemi_system_reset_exception <-.system_reset_exception <idle>-0 [000] 1558.861109: .pasemi_system_reset_exception <-.system_reset_exception <idle>-0 [001] 1558.861361: .pasemi_system_reset_exception <-.system_reset_exception <idle>-0 [000] 1558.861437: .pasemi_system_reset_exception <-.system_reset_exception When the region is unmapped, the system crashes with: Disabling non-boot CPUs ... Error taking CPU1 down: -38 Unable to handle kernel paging request for data at address 0xd0000800903a0100 Faulting instruction address: 0xc000000000055fcc Oops: Kernel access of bad area, sig: 11 [#1] PREEMPT SMP NR_CPUS=64 NUMA PA Semi PWRficient Modules linked in: shpchp NIP: c000000000055fcc LR: c000000000055fb4 CTR: c0000000000df1fc REGS: c0000000012175d0 TRAP: 0300 Not tainted (3.8.0-rc4-test-dirty) MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI> CR: 24000088 XER: 00000000 SOFTE: 0 DAR: d0000800903a0100, DSISR: 42000000 TASK = c0000000010e9008[0] 'swapper/0' THREAD: c000000001214000 CPU: 0 GPR00: d0000800903a0000 c000000001217850 c0000000012167e0 0000000000000000 GPR04: 0000000000000000 0000000000000724 0000000000000724 0000000000000000 GPR08: 0000000000000000 0000000000000000 0000000000000001 0000000000a70000 GPR12: 0000000024000080 c00000000fff0000 ffffffffffffffff 000000003ffffae0 GPR16: ffffffffffffffff 0000000000a21198 0000000000000060 0000000000000000 GPR20: 00000000008fdd35 0000000000a21258 000000003ffffaf0 0000000000000417 GPR24: 0000000000a226d0 c000000000000000 0000000000000000 0000000000000000 GPR28: c00000000138b358 0000000000000000 c000000001144818 d0000800903a0100 NIP [c000000000055fcc] .set_astate+0x5c/0xa4 LR [c000000000055fb4] .set_astate+0x44/0xa4 Call Trace: [c000000001217850] [c000000000055fb4] .set_astate+0x44/0xa4 (unreliable) [c0000000012178f0] [c00000000005647c] .restore_astate+0x2c/0x34 [c000000001217980] [c000000000054668] .pasemi_system_reset_exception+0x6c/0x88 [c000000001217a00] [c000000000019ef0] .system_reset_exception+0x48/0x84 [c000000001217a80] [c000000000001e40] system_reset_common+0x140/0x180 Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> 
commit f96972f2dc "kernel/sys.c: call disable_nonboot_cpus() in
kernel_restart()"

added a call to disable_nonboot_cpus() on kernel_restart(), which tries
to shutdown all the CPUs except the first one. The issue with the PA
Semi, is that it does not support CPU hotplug.

When the call is made to __cpu_down(), it calls the notifiers
CPU_DOWN_PREPARE, and then tries to take the CPU down.

One of the notifiers to the CPU hotplug code, is the cpufreq. The
DOWN_PREPARE will call __cpufreq_remove_dev() which calls
cpufreq_driver->exit. The PA Semi exit handler unmaps regions of I/O
that is used by an interrupt that goes off constantly
(system_reset_common, but it goes off during normal system operations
too). I'm not sure exactly what this interrupt does.

Running a simple function trace, you can see it goes off quite a bit:

# tracer: function
#
#           TASK-PID    CPU#    TIMESTAMP  FUNCTION
#              | |       |          |         |
          <idle>-0     [001]  1558.859363: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [000]  1558.860112: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [000]  1558.861109: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [001]  1558.861361: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [000]  1558.861437: .pasemi_system_reset_exception <-.system_reset_exception

When the region is unmapped, the system crashes with:

Disabling non-boot CPUs ...
Error taking CPU1 down: -38
Unable to handle kernel paging request for data at address 0xd0000800903a0100
Faulting instruction address: 0xc000000000055fcc
Oops: Kernel access of bad area, sig: 11 [#1]
PREEMPT SMP NR_CPUS=64 NUMA PA Semi PWRficient
Modules linked in: shpchp
NIP: c000000000055fcc LR: c000000000055fb4 CTR: c0000000000df1fc
REGS: c0000000012175d0 TRAP: 0300   Not tainted  (3.8.0-rc4-test-dirty)
MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI>  CR: 24000088  XER: 00000000
SOFTE: 0
DAR: d0000800903a0100, DSISR: 42000000
TASK = c0000000010e9008[0] 'swapper/0' THREAD: c000000001214000 CPU: 0
GPR00: d0000800903a0000 c000000001217850 c0000000012167e0 0000000000000000
GPR04: 0000000000000000 0000000000000724 0000000000000724 0000000000000000
GPR08: 0000000000000000 0000000000000000 0000000000000001 0000000000a70000
GPR12: 0000000024000080 c00000000fff0000 ffffffffffffffff 000000003ffffae0
GPR16: ffffffffffffffff 0000000000a21198 0000000000000060 0000000000000000
GPR20: 00000000008fdd35 0000000000a21258 000000003ffffaf0 0000000000000417
GPR24: 0000000000a226d0 c000000000000000 0000000000000000 0000000000000000
GPR28: c00000000138b358 0000000000000000 c000000001144818 d0000800903a0100
NIP [c000000000055fcc] .set_astate+0x5c/0xa4
LR [c000000000055fb4] .set_astate+0x44/0xa4
Call Trace:
[c000000001217850] [c000000000055fb4] .set_astate+0x44/0xa4 (unreliable)
[c0000000012178f0] [c00000000005647c] .restore_astate+0x2c/0x34
[c000000001217980] [c000000000054668] .pasemi_system_reset_exception+0x6c/0x88
[c000000001217a00] [c000000000019ef0] .system_reset_exception+0x48/0x84
[c000000001217a80] [c000000000001e40] system_reset_common+0x140/0x180

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc: Fix MAX_STACK_TRACE_ENTRIES too low warning for ppc32 2013-01-28T23:10:22+00:00 Li Zhong zhong@linux.vnet.ibm.com 2012-12-02T20:19:22+00:00 41d82bdb40af74a88cff4589ea7a60091b11070e This patch fixes MAX_STACK_TRACE_ENTRIES too low warning for ppc32, which is similar to commit 12660b17. Reported-by: Christian Kujau <lists@nerdbynature.de> Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Tested-by: Christian Kujau <lists@nerdbynature.de> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> 
This patch fixes MAX_STACK_TRACE_ENTRIES too low warning for ppc32,
which is similar to commit 12660b17.

Reported-by: Christian Kujau <lists@nerdbynature.de>
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Tested-by: Christian Kujau <lists@nerdbynature.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
KVM: PPC: Emulate dcbf 2013-01-17T23:40:49+00:00 Alexander Graf agraf@suse.de 2013-01-17T12:50:25+00:00 d3286144c92ec876da9e30320afa875699b7e0f1 Guests can trigger MMIO exits using dcbf. Since we don't emulate cache incoherent MMIO, just do nothing and move on. Reported-by: Ben Collins <ben.c@servergy.com> Signed-off-by: Alexander Graf <agraf@suse.de> Tested-by: Ben Collins <ben.c@servergy.com> CC: stable@vger.kernel.org 
Guests can trigger MMIO exits using dcbf. Since we don't emulate cache
incoherent MMIO, just do nothing and move on.

Reported-by: Ben Collins <ben.c@servergy.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Tested-by: Ben Collins <ben.c@servergy.com>
CC: stable@vger.kernel.org
Merge git://git.kernel.org/pub/scm/virt/kvm/kvm 2013-01-10T17:05:18+00:00 Linus Torvalds torvalds@linux-foundation.org 2013-01-10T17:05:18+00:00 ccae663cd4f62890d862c660e5ed762eb9821c14 Pull KVM bugfixes from Marcelo Tosatti. * git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: use dynamic percpu allocations for shared msrs area KVM: PPC: Book3S HV: Fix compilation without CONFIG_PPC_POWERNV powerpc: Corrected include header path in kvm_para.h Add rcu user eqs exception hooks for async page fault 
Pull KVM bugfixes from Marcelo Tosatti.

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: use dynamic percpu allocations for shared msrs area
  KVM: PPC: Book3S HV: Fix compilation without CONFIG_PPC_POWERNV
  powerpc: Corrected include header path in kvm_para.h
  Add rcu user eqs exception hooks for async page fault
KVM: PPC: Book3S HV: Fix compilation without CONFIG_PPC_POWERNV 2013-01-06T13:02:00+00:00 Andreas Schwab schwab@linux-m68k.org 2012-12-22T04:09:17+00:00 d591390da94234d5b8eb1bbd9f2a25d2e780d528 Fixes this build breakage: arch/powerpc/kvm/book3s_hv_ras.c: In function ‘kvmppc_realmode_mc_power7’: arch/powerpc/kvm/book3s_hv_ras.c:126:23: error: ‘struct paca_struct’ has no member named ‘opal_mc_evt’ Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Alexander Graf <agraf@suse.de> 
Fixes this build breakage:

arch/powerpc/kvm/book3s_hv_ras.c: In function ‘kvmppc_realmode_mc_power7’:
arch/powerpc/kvm/book3s_hv_ras.c:126:23: error: ‘struct paca_struct’ has no member named ‘opal_mc_evt’

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Alexander Graf <agraf@suse.de>