kdump/kexec kernel
Summary:
Asserting INIT on the beginning of kdump/kexec kernel will result
in unexpected behavior because INIT handler for previous kernel is
invoked on new kernel.
Description:
In panic situation, we can receive INIT while kernel transition,
i.e. from beginning of panic to bootstrap of kdump kernel.
Since we initialize registers on leave from current kernel, no
longer monarch/slave handlers of current kernel in virtual mode are
called safely. (In fact system goes hang as far as I confirmed)
How to Reproduce:
Start kdump
# echo c > /proc/sysrq-trigger
Then assert INIT while kdump kernel is booting, before new INIT
handler for kdump kernel is registered.
Expected(Desirable) result:
kdump kernel boots without any problem, crashdump retrieved
Actual result:
INIT handler for previous kernel is invoked on kdump kernel
=> panic, hang etc. (unexpected)
Proposed fix:
We can unregister these init handlers from SAL before jumping into
new kernel, however then the INIT will fallback to default behavior,
result in warmboot by SAL (according to the SAL specification) and
we cannot retrieve the crashdump.
Therefore this patch introduces a NOP init handler and register it
to SAL before leave from current kernel, to start kdump safely by
preventing INITs from entering virtual mode and resulting in warmboot.
On the other hand, in case of kexec that not for kdump, it also
has same problem with INIT while kernel transition.
This patch handles this case differently, because for kexec
unregistering handlers will be preferred than registering NOP
handler, since the situation "no handlers registered" is usual
state for kernel's entry.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: kexec@lists.infradead.org
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Summary:
INIT asserted on kdump kernel invokes INIT handler not only on a
cpu that running on the kdump kernel, but also BSP of the panicked
kernel, because the (badly) frozen BSP can be thawed by INIT.
Description:
The kdump_cpu_freeze() is called on cpus except one that initiates
panic and/or kdump, to stop/offline the cpu (on ia64, it means we
pass control of cpus to SAL, or put them in spinloop). Note that
CPU0(BSP) always go to spinloop, so if panic was happened on an AP,
there are at least 2cpus (= the AP and BSP) which not back to SAL.
On the spinning cpus, interrupts are disabled (rsm psr.i), but INIT
is still interruptible because psr.mc for mask them is not set unless
kdump_cpu_freeze() is not called from MCA/INIT context.
Therefore, assume that a panic was happened on an AP, kdump was
invoked, new INIT handlers for kdump kernel was registered and then
an INIT is asserted. From the viewpoint of SAL, there are 2 online
cpus, so INIT will be delivered to both of them. It likely means
that not only the AP (= a cpu executing kdump) enters INIT handler
which is newly registered, but also BSP (= another cpu spinning in
panicked kernel) enters the same INIT handler. Of course setting of
registers in BSP are still old (for panicked kernel), so what happen
with running handler with wrong setting will be extremely unexpected.
I believe this is not desirable behavior.
How to Reproduce:
Start kdump on one of APs (e.g. cpu1)
# taskset 0x2 echo c > /proc/sysrq-trigger
Then assert INIT after kdump kernel is booted, after new INIT handler
for kdump kernel is registered.
Expected results:
An INIT handler is invoked only on the AP.
Actual results:
An INIT handler is invoked on the AP and BSP.
Sample of results:
I got following console log by asserting INIT after prompt "root:/>".
It seems that two monarchs appeared by one INIT, and one panicked at
last. And it also seems that the panicked one supposed there were
4 online cpus and no one did rendezvous:
:
[ 0 %]dropping to initramfs shell
exiting this shell will reboot your system
root:/> Entered OS INIT handler. PSP=fff301a0 cpu=0 monarch=0
ia64_init_handler: Promoting cpu 0 to monarch.
Delaying for 5 seconds...
All OS INIT slaves have reached rendezvous
Processes interrupted by INIT - 0 (cpu 0 task 0xa000000100af0000)
:
<<snip>>
:
Entered OS INIT handler. PSP=fff301a0 cpu=0 monarch=1
Delaying for 5 seconds...
mlogbuf_finish: printing switched to urgent mode, MCA/INIT might be dodgy or fail.
OS INIT slave did not rendezvous on cpu 1 2 3
INIT swapper 0[0]: bugcheck! 0 [1]
:
<<snip>>
:
Kernel panic - not syncing: Attempted to kill the idle task!
Proposed fix:
To avoid this problem, this patch inserts ia64_set_psr_mc() to mask
INIT on cpus going to be frozen. This masking have no effect if the
kdump_cpu_freeze() is called from INIT handler when kdump_on_init == 1,
because psr.mc is already turned on to 1 before entering OS_INIT.
I confirmed that weird log like above are disappeared after applying
this patch.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: kexec@lists.infradead.org
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1623 commits)
netxen: update copyright
netxen: fix tx timeout recovery
netxen: fix file firmware leak
netxen: improve pci memory access
netxen: change firmware write size
tg3: Fix return ring size breakage
netxen: build fix for INET=n
cdc-phonet: autoconfigure Phonet address
Phonet: back-end for autoconfigured addresses
Phonet: fix netlink address dump error handling
ipv6: Add IFA_F_DADFAILED flag
net: Add DEVTYPE support for Ethernet based devices
mv643xx_eth.c: remove unused txq_set_wrr()
ucc_geth: Fix hangs after switching from full to half duplex
ucc_geth: Rearrange some code to avoid forward declarations
phy/marvell: Make non-aneg speed/duplex forcing work for 88E1111 PHYs
drivers/net/phy: introduce missing kfree
drivers/net/wan: introduce missing kfree
net: force bridge module(s) to be GPL
Subject: [PATCH] appletalk: Fix skb leak when ipddp interface is not loaded
...
Fixed up trivial conflicts:
- arch/x86/include/asm/socket.h
converted to <asm-generic/socket.h> in the x86 tree. The generic
header has the same new #define's, so that works out fine.
- drivers/net/tun.c
fix conflict between 89f56d1e9 ("tun: reuse struct sock fields") that
switched over to using 'tun->socket.sk' instead of the redundantly
available (and thus removed) 'tun->sk', and 2b980dbd ("lsm: Add hooks
to the TUN driver") which added a new 'tun->sk' use.
Noted in 'next' by Stephen Rothwell.
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (28 commits)
rcu: Move end of special early-boot RCU operation earlier
rcu: Changes from reviews: avoid casts, fix/add warnings, improve comments
rcu: Create rcutree plugins to handle hotplug CPU for multi-level trees
rcu: Remove lockdep annotations from RCU's _notrace() API members
rcu: Add #ifdef to suppress __rcu_offline_cpu() warning in !HOTPLUG_CPU builds
rcu: Add CPU-offline processing for single-node configurations
rcu: Add "notrace" to RCU function headers used by ftrace
rcu: Remove CONFIG_PREEMPT_RCU
rcu: Merge preemptable-RCU functionality into hierarchical RCU
rcu: Simplify rcu_pending()/rcu_check_callbacks() API
rcu: Use debugfs_remove_recursive() simplify code.
rcu: Merge per-RCU-flavor initialization into pre-existing macro
rcu: Fix online/offline indication for rcudata.csv trace file
rcu: Consolidate sparse and lockdep declarations in include/linux/rcupdate.h
rcu: Renamings to increase RCU clarity
rcu: Move private definitions from include/linux/rcutree.h to kernel/rcutree.h
rcu: Expunge lingering references to CONFIG_CLASSIC_RCU, optimize on !SMP
rcu: Delay rcu_barrier() wait until beginning of next CPU-hotunplug operation.
rcu: Fix typo in rcu_irq_exit() comment header
rcu: Make rcupreempt_trace.c look at offline CPUs
...
* 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (59 commits)
x86/gart: Do not select AGP for GART_IOMMU
x86/amd-iommu: Initialize passthrough mode when requested
x86/amd-iommu: Don't detach device from pt domain on driver unbind
x86/amd-iommu: Make sure a device is assigned in passthrough mode
x86/amd-iommu: Align locking between attach_device and detach_device
x86/amd-iommu: Fix device table write order
x86/amd-iommu: Add passthrough mode initialization functions
x86/amd-iommu: Add core functions for pd allocation/freeing
x86/dma: Mark iommu_pass_through as __read_mostly
x86/amd-iommu: Change iommu_map_page to support multiple page sizes
x86/amd-iommu: Support higher level PTEs in iommu_page_unmap
x86/amd-iommu: Remove old page table handling macros
x86/amd-iommu: Use 2-level page tables for dma_ops domains
x86/amd-iommu: Remove bus_addr check in iommu_map_page
x86/amd-iommu: Remove last usages of IOMMU_PTE_L0_INDEX
x86/amd-iommu: Change alloc_pte to support 64 bit address space
x86/amd-iommu: Introduce increase_address_space function
x86/amd-iommu: Flush domains if address space size was increased
x86/amd-iommu: Introduce set_dte_entry function
x86/amd-iommu: Add a gneric version of amd_iommu_flush_all_devices
...
Remove kvm_cpu_has_interrupt() and kvm_arch_interrupt_allowed() from
interface between general code and arch code. kvm_arch_vcpu_runnable()
checks for interrupts instead.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This changes bus accesses to use high-level kvm_io_bus_read/kvm_io_bus_write
functions. in_range now becomes unused so it is removed from device ops in
favor of read/write callbacks performing range checks internally.
This allows aliasing (mostly for in-kernel virtio), as well as better error
handling by making it possible to pass errors up to userspace.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Archs are free to use vcpu_id as they see fit. For x86 it is used as
vcpu's apic id. New ioctl is added to configure boot vcpu id that was
assumed to be 0 till now.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Protect irq injection/acking data structures with a separate irq_lock
mutex. This fixes the following deadlock:
CPU A CPU B
kvm_vm_ioctl_deassign_dev_irq()
mutex_lock(&kvm->lock); worker_thread()
-> kvm_deassign_irq() -> kvm_assigned_dev_interrupt_work_handler()
-> deassign_host_irq() mutex_lock(&kvm->lock);
-> cancel_work_sync() [blocked]
[gleb: fix ia64 path]
Reported-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Init the itc_offset for all possible vCPUs. The current code by
mistake ends up only initializing the offset on vCPU 0.
Spotted by Gleb Natapov.
Signed-off-by: Jes Sorensen <jes@sgi.com>
Acked-by : Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This was #define'd as 0 on all platforms, so let's get rid of it.
This change makes pci_scan_slot() slightly easier to read.
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Luck <tony.luck@intel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The 32-bit parameters (len and csum) of csum_ipv6_magic() are passed in 64-bit
registers in2 and in4. The high order 32 bits of the registers were never
cleared, and garbage was sometimes calculated into the checksum.
Fix this by clearing the high order 32 bits of these registers.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: Tony Luck <tony.luck@intel.com>
arch/ia64/kernel/dma-mapping.c:14: warning: control reaches end of non-void function
arch/ia64/kernel/dma-mapping.c:14: warning: no return statement in function returning non-void
This warning was introduced by commit: 390bd132b2831a2ad0268e84bffbfc0680debfe5
Add dma_debug_init() for ia64
Signed-off-by: Tony Luck <tony.luck@intel.com>
Add a keyctl to install a process's session keyring onto its parent. This
replaces the parent's session keyring. Because the COW credential code does
not permit one process to change another process's credentials directly, the
change is deferred until userspace next starts executing again. Normally this
will be after a wait*() syscall.
To support this, three new security hooks have been provided:
cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
the blank security creds and key_session_to_parent() - which asks the LSM if
the process may replace its parent's session keyring.
The replacement may only happen if the process has the same ownership details
as its parent, and the process has LINK permission on the session keyring, and
the session keyring is owned by the process, and the LSM permits it.
Note that this requires alteration to each architecture's notify_resume path.
This has been done for all arches barring blackfin, m68k* and xtensa, all of
which need assembly alteration to support TIF_NOTIFY_RESUME. This allows the
replacement to be performed at the point the parent process resumes userspace
execution.
This allows the userspace AFS pioctl emulation to fully emulate newpag() and
the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
alter the parent process's PAG membership. However, since kAFS doesn't use
PAGs per se, but rather dumps the keys into the session keyring, the session
keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
the newpag flag.
This can be tested with the following program:
#include <stdio.h>
#include <stdlib.h>
#include <keyutils.h>
#define KEYCTL_SESSION_TO_PARENT 18
#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)
int main(int argc, char **argv)
{
key_serial_t keyring, key;
long ret;
keyring = keyctl_join_session_keyring(argv[1]);
OSERROR(keyring, "keyctl_join_session_keyring");
key = add_key("user", "a", "b", 1, keyring);
OSERROR(key, "add_key");
ret = keyctl(KEYCTL_SESSION_TO_PARENT);
OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");
return 0;
}
Compiled and linked with -lkeyutils, you should see something like:
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: _ses
355907932 --alswrv 4043 -1 \_ keyring: _uid.4043
[dhowells@andromeda ~]$ /tmp/newpag
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: _ses
1055658746 --alswrv 4043 4043 \_ user: a
[dhowells@andromeda ~]$ /tmp/newpag hello
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: hello
340417692 --alswrv 4043 4043 \_ user: a
Where the test program creates a new session keyring, sticks a user key named
'a' into it and then installs it on its parent.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Completed a major update for the acpi_get_object_info external interface.
Changes include:
- Support for variable, unlimited length HID, UID, and CID strings
- Support Processor objects the same as Devices (HID,UID,CID,ADR,STA, etc.)
- Call the _SxW power methods on behalf of a device object
- Determine if a device is a PCI root bridge
- Change the ACPI_BUFFER parameter to ACPI_DEVICE_INFO.
These changes will require an update to all callers of this interface.
See the ACPICA Programmer Reference for details.
Also, update all invocations of acpi_get_object_info interface
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Reason: Change to is_new_memtype_allowed() in x86/urgent
Resolved semantic conflicts in:
arch/x86/mm/pat.c
arch/x86/mm/ioremap.c
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Only IA64 was using PG_uncached as of now. We now intend to use this bit
in x86 as well, to keep track of memory type of those addresses that
have page struct for them. So, generalize the use of that bit across
ia64 and x86.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Conflicts:
arch/sparc/kernel/smp_64.c
arch/x86/kernel/cpu/perf_counter.c
arch/x86/kernel/setup_percpu.c
drivers/cpufreq/cpufreq_ondemand.c
mm/percpu.c
Conflicts in core and arch percpu codes are mostly from commit
ed78e1e078dd44249f88b1dd8c76dafb39567161 which substituted many
num_possible_cpus() with nr_cpu_ids. As for-next branch has moved all
the first chunk allocators into mm/percpu.c, the changes are moved
from arch code to mm/percpu.c.
Signed-off-by: Tejun Heo <tj@kernel.org>
Since commit 19943b0e30b05d42e494ae6fef78156ebc8c637e ('intel-iommu:
Unify hardware and software passthrough support'), hardware passthrough
mode will do the same as software passthrough mode was doing -- it'll
still use the IOMMU normally for devices which can't address all of
memory. This means that we don't need to bother with swiotlb.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Between GCC version 3.4.0 and 4.3.3 (including 3.4.0 and 4.3.3), -mtune=merced
is implemented in GCC. Starting from 4.4.0, -mtune=merced is deprecated.
Even implemented in versions between 3.4.0 and 4.3.3, the -mtune=merced
feature has been broken in some of the versions. For example, GCC 4.1.2 reports
interanl tuning function errors during kernel building with -mtune=merced. Or
GCC Bugzilla 16130 reports another -mtune=merced issue on GCC 3.4.1.
So I would remove the -mtune=merced from IA64 kernel build. Without this option,
kernel on Merced will remain the same except losing an unstable and out-of-date
performance tunning feature.
Since GCC version 3.4.0, -mtune=mckinley has been implemented. The
-mtune=mckinley option functions the same as mtune=itanium2. And mtune=itanium2
is the default option. So we don't need to add mtune=mckinley either since its
been the default option in any GCC version which implements this option.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
fix the following 'make includecheck' warning:
arch/ia64/include/asm/pgtable.h: asm/processor.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
fix the following 'make includecheck' warning:
arch/ia64/kernel/ia64_ksyms.c: asm/page.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
__test_and_clear_bit() returns a bitfield with the tested-for bit set.
Make it consistent with the other bitops - of ia64 but also every
other architecture - and return a boolean value.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
In commit 160c1d8e40866edfeae7d68816b7005d70acf391,
dma_ops->dma_supported = iommu_dma_supported;
This dma_ops->dma_supported is first called in platform_dma_init() during kernel
boot. Then dma_ops->dma_supported will be called recursively in
iommu_dma_supported.
Kernel can not boot because kernel can not get out of iommu_dma_supported until
it runs out of stack memory.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
flush_write_buffers() in dma-mapping-common.h was removed so we
can remove NULL flush_write_buffers() in IA64.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: davem@davemloft.net
LKML-Reference: <1249872797-1314-3-git-send-email-fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This sockopt goes in line with SO_TYPE and SO_PROTOCOL. It makes it
possible for userspace programs to pass around file descriptors — I
am referring to arguments-to-functions, but it may even work for the
fd passing over UNIX sockets — without needing to also pass the
auxiliary information (PF_INET6/IPPROTO_TCP).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to SO_TYPE returning the socket type, SO_PROTOCOL allows to
retrieve the protocol used with a given socket.
I am not quite sure why we have that-many copies of socket.h, and why
the values are not the same on all arches either, but for where hex
numbers dominate, I use 0x1029 for SO_PROTOCOL as that seems to be
the next free unused number across a bunch of operating systems, or
so Google results make me want to believe. SO_PROTOCOL for others
just uses the next free Linux number, 38.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
For powerpc with CONFIG_VIRT_CPU_ACCOUNTING
jiffies_to_cputime(1) is not compile time constant and run time
calculations are quite expensive. To optimize we use
precomputed value. For all other architectures is is
preprocessor definition.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
LKML-Reference: <1248862529-6063-5-git-send-email-sgruszka@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This adds two functions, phys_to_dma() and dma_to_phys() to x86, IA64
and powerpc. swiotlb uses them. phys_to_dma() converts a physical
address to a dma address. dma_to_phys() does the opposite.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
dma_capable() eventually replaces is_buffer_dma_capable(), which tells
if a memory area is dma-capable or not. The problem of
is_buffer_dma_capable() is that it doesn't take a pointer to struct
device so it doesn't work for POWERPC.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>