Currently it uses a single static char array, but that risks
being corrupted when multiple users issue message notes at the
same time. Make the buffers dynamically allocated when the trace
is setup and make them per-cpu instead.
The default max message size of 1k is also very large, the
interface is mainly for small text notes. So shrink it to 128 bytes.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Allows messages to be inserted into blktrace streams.
Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
saves 8 bytes of padding & increases objects/slab from 30 to 32 on my
AMD64 config
Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
In function get_request_wait, the second call to get_request could be
moved to the end of the while loop, because if the first call to
get_request fails, the second call will fail without sleep.
Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
splice currently assumes that try_to_release_page() always suceeds,
but it can return failure. If it does, we cannot steal the page.
Acked-by: Mingming Cao <cmm@us.ibm.com
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Splice isn't always incrementing the ppos correctly, which broke
relay splice.
Signed-off-by: Tom Zanussi <zanussi@comcast.net>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
-tip tree auto-testing found the following early bootup hang:
-------------->
get_memcfg_from_srat: assigning address to rsdp
RSD PTR v0 [Nvidia]
BUG: Int 14: CR2 ffd00040
EDI 8092fbfe ESI ffd00040 EBP 80b0aee8 ESP 80b0aed0
EBX 000f76f0 EDX 0000000e ECX 00000003 EAX ffd00040
err 00000000 EIP 802c055a CS 00000060 flg 00010006
Stack: ffd00040 80bc78d0 80b0af6c 80b1dbfe 8093d8ba 00000008 80b42810 80b4ddb4
80b42842 00000000 80b0af1c 801079c8 808e724e 00000000 80b42871 802c0531
00000100 00000000 0003fff0 80b0af40 80129999 00040100 00040100 00000000
Pid: 0, comm: swapper Not tainted 2.6.26-rc4-sched-devel.git #570
[<802c055a>] ? strncmp+0x11/0x25
[<80b1dbfe>] ? get_memcfg_from_srat+0xb4/0x568
[<801079c8>] ? mcount_call+0x5/0x9
[<802c0531>] ? strcmp+0xa/0x22
[<80129999>] ? printk+0x38/0x3a
[<80129999>] ? printk+0x38/0x3a
[<8011b122>] ? memory_present+0x66/0x6f
[<80b216b4>] ? setup_memory+0x13/0x40c
[<80b16b47>] ? propagate_e820_map+0x80/0x97
[<80b1622a>] ? setup_arch+0x248/0x477
[<80129999>] ? printk+0x38/0x3a
[<80b11759>] ? start_kernel+0x6e/0x2eb
[<80b110fc>] ? i386_start_kernel+0xeb/0xf2
=======================
<------
with this config:
http://redhat.com/~mingo/misc/config-Wed_May_28_01_33_33_CEST_2008.bad
The thing is, the crash makes little sense at first sight. We crash on a
benign-looking printk. The code around it got changed in -tip but
checking those topic branches individually did not reproduce the bug.
Bisection led to this commit:
| d5edbc1f75 is first bad commit
| commit d5edbc1f75
| Author: Jeremy Fitzhardinge <jeremy@goop.org>
| Date: Mon May 26 23:31:22 2008 +0100
|
| xen: add p2m mfn_list_list
Which is somewhat surprising, as on native hardware Xen client side
should have little to no side-effects.
After some head scratching, it turns out the following happened:
randconfig enabled the following Xen options:
CONFIG_XEN=y
CONFIG_XEN_MAX_DOMAIN_MEMORY=8
# CONFIG_XEN_BLKDEV_FRONTEND is not set
# CONFIG_XEN_NETDEV_FRONTEND is not set
CONFIG_HVC_XEN=y
# CONFIG_XEN_BALLOON is not set
which activated this piece of code in arch/x86/xen/mmu.c:
> @@ -69,6 +69,13 @@
> __attribute__((section(".data.page_aligned"))) =
> { [ 0 ... TOP_ENTRIES - 1] = &p2m_missing[0] };
>
> +/* Arrays of p2m arrays expressed in mfns used for save/restore */
> +static unsigned long p2m_top_mfn[TOP_ENTRIES]
> + __attribute__((section(".bss.page_aligned")));
> +
> +static unsigned long p2m_top_mfn_list[TOP_ENTRIES / P2M_ENTRIES_PER_PAGE]
> + __attribute__((section(".bss.page_aligned")));
The problem is, you must only put variables into .bss.page_aligned that
have a _size_ that is _exactly_ page aligned. In this case the size of
p2m_top_mfn_list is not page aligned:
80b8d000 b p2m_top_mfn
80b8f000 b p2m_top_mfn_list
80b8f008 b softirq_stack
80b97008 b hardirq_stack
80b9f008 b bm_pte
So all subsequent variables get unaligned which, depending on luck,
breaks the kernel in various funny ways. In this case what killed the
kernel first was the misaligned bootmap pte page, resulting in that
creative crash above.
Anyway, this was a fun bug to track down :-)
I think the moral is that .bss.page_aligned is a dangerous construct in
its current form, and the symptoms of breakage are very non-trivial, so
i think we need build-time checks to make sure all symbols in
.bss.page_aligned are truly page aligned.
The Xen fix below gets the kernel booting again.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
pciehp: add message about pciehp_slot_with_bus option
pci hotplug core: add check of duplicate slot name
pciehp: move msleep after power off
pciehp: poll cmd completion if hotplug interrupt is disabled
pciehp: fix slow probing
pciehp: fix NULL dereference in interrupt handler
shpchp: add message about shpchp_slot_with_bus option
PCI: don't enable ASPM on devices with mixed PCIe/PCI functions
Some (broken?) platform assign the same slot name to multiple hotplug
slots. On such system, slot initialization would fail because of name
collision. The pciehp driver already have a "slot_with_bus" module
option which adds the bus number into the slot name. This patch adds
the message about this module option that will be displayed when slot
name collision is detected.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Fix the following errors reported by Jan C. Nordholz in
http://bugzilla.kernel.org/show_bug.cgi?id=10751.
kobject_add_internal failed for 2 with -EEXIST, don't try to register things with the same name in the same directory.
Pid: 1, comm: swapper Tainted: G W 2.6.26-rc3 #1
[<c0266980>] kobject_add_internal+0x140/0x190
[<c0266afd>] kobject_init_and_add+0x2d/0x40
[<c027bc91>] pci_hp_register+0x81/0x2f0
[<c027fd07>] pciehp_probe+0x1a7/0x470
[<c01b3b84>] sysfs_add_one+0x44/0xa0
[<c01b3c1f>] sysfs_addrm_start+0x3f/0xb0
[<c01b497a>] sysfs_create_link+0x8a/0xf0
[<c0279570>] pcie_port_probe_service+0x50/0x80
[<c02e0545>] driver_sysfs_add+0x55/0x70
[<c02e0662>] driver_probe_device+0x82/0x180
[<c02e07cc>] __driver_attach+0x6c/0x70
[<c02dfe0a>] bus_for_each_dev+0x3a/0x60
[<c05db2d0>] pcied_init+0x0/0x80
[<c02e04e6>] driver_attach+0x16/0x20
[<c02e0760>] __driver_attach+0x0/0x70
[<c02e0341>] bus_add_driver+0x1a1/0x220
[<c05db2d0>] pcied_init+0x0/0x80
[<c02e09cd>] driver_register+0x4d/0x120
[<c05db050>] ibm_acpiphp_init+0x0/0x190
[<c0125aab>] printk+0x1b/0x20
[<c05db2d0>] pcied_init+0x0/0x80
[<c05db2de>] pcied_init+0xe/0x80
[<c05c751a>] kernel_init+0x10a/0x300
[<c0120138>] schedule_tail+0x18/0x50
[<c0103b9a>] ret_from_fork+0x6/0x1c
[<c05c7410>] kernel_init+0x0/0x300
[<c05c7410>] kernel_init+0x0/0x300
[<c010485b>] kernel_thread_helper+0x7/0x1c
=======================
pci_hotplug: Unable to register kobject '2'<3>pciehp: pci_hp_register failed with error -22
Slot with the same name can be registered multiple times if shpchp or
pciehp driver is loaded after acpiphp is loaded because ACPI based
hotplug driver and Native OS hotplug driver trying to handle the same
physical slot. In this case, current pci_hotplug core will call
kobject_init_and_add() muliple time with the same name. This is the
cause of this problem. To fix this problem, this patch adds the check
into pci_hp_register() to see if the slot with the same name.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
According to the PCI Express specification, we must wait for at least
1 second after turning power off before taking any action that relies
on power having been removed from the slot/adapter. For this, current
pciehp wait for 1 second after issuing the power off command in
hpc_power_off_slot() function. But waiting for 1 second in
hpc_power_off_slot() can make pciehp probing slow-down because pciehp
probe code calls hpc_power_off_slot() if the slot is not occupied just
in case. We don't need to wait for 1 second at the pciehp probe time
because there is no action on that empty slot. So move 1 second wait
from hpc_power_off_slot() to the caller of hpc_power_off_slot().
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Fix improper long wait for command completion in pciehp probing.
As described in PCI Express specification, software notification is
not generated if the command that occurs as a result of a write to the
Slot Control register that disables software notification of command
completed events. Since pciehp driver doesn't take it into account,
such command is issued in pciehp probing, and it causes improper long
wait for command completion.
This patch changes the pciehp driver to take such command into
account.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Fix the "pciehp probing slow" problem reported from Jan C. Nordholz in
http://bugzilla.kernel.org/show_bug.cgi?id=10751.
The command completed bit in Slot Status register applies only to
commands issued to control the attention indicator, power indicator,
power controller, or electromechanical interlock. However, writes to
other parts of the Slot Control register would end up writing to the
control fields. Hence, any write to Slot Control register is
considered as a command. However, if the controller doesn't support
any of attention indicator, power indicator, power controller and
electromechanical interlock, command completed bit would not set in
writing to Slot Control register. In this case, we should not wait for
command completed bit set, otherwise all commands would be considered
not completed in timeout seconds (1 sec.).
The cause of the problem is pciehp driver didn't take this situation
into account. This patch changes pciehp to take it into account. This
patch also add the check for "No Command Completed Support" bit in
Slot Capability register. If it is set, we should not wait for command
completed bit set as well.
This problem seems to be revealed by the commit
c27fb883df that fixed the bug that
pciehp did not wait for command completed properly (pciehp just
ignored the command completion event).
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Some (broken?) platform assign the same slot name to multiple hotplug
slots. On such system, slot initialization would fail because of name
collision. The shpchp driver already have a "slot_with_bus" module
option which adds the bus number into the slot name. This patch adds
the message about this module option that will be displayed when slot
name collision is detected.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Documentation on ia64/pv_ops which describes its strategy and implementation.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Cc: Gerald Pfeifer <gp@novell.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Introduce pv_time_ops which adds hook to steal time accounting.
On virtualized environment, cpus are shared by many guests and
steal time is the time which is used for other guests.
On virtualized environtment, streal time should be accounted.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
introduce pv_irq_ops which adds hooks to paravirtualize irq related
operations.
On virtualized environment, interruption may be replaced by something
virtualization friendly. So the irq related operation also may need
paravirtualization.
This patch adds necessary hooks to paravirtualize irq related operations.
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
add hooks to paravirtualize iosapic which is a real hardware resource.
On virtualized environment it may be replaced something virtualized
friendly.
Define pv_iosapic_ops and add the hooks.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
define pv_init_ops hooks which represents various initialization
hooks for paravirtualized environment. and add hooks.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Make NR_IRQ overridable by each pv instances.
Pv instance may need each own number of irqs so that
NR_IRQS should be the maximum number of nr_irqs each
pv instances need.
Cc: Jes Sorensen <jes@sgi.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
paravirtualize ia64_swtich_to, ia64_leave_syscall and ia64_leave_kernel.
They include sensitive or performance critical privileged instructions
so that they need paravirtualization.
To paravirtualize them by single source and multi compile
they are converted into indirect jump. And define each pv instances.
Cc: Keith Owens <kaos@ocs.com.au>
Cc: "Dong, Eddie" <eddie.dong@intel.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
paravirtualize ivt.S which implements fault handler in hand written
assembly code.
They includes sensitive or performance critical privileged instructions.
So they need paravirtualization.
Cc: Keith Owens <kaos@ocs.com.au>
Cc: tgingold@free.fr
Cc: Akio Takebe <takebe_akio@jp.fujitsu.com>
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
paravirtualize minstate.h which are hand written assembly code.
They include sensitive or performance critical privileged
instructions. So that they are appropriate for paravirtualization.
Cc: Keith Owens <kaos@ocs.com.au>
Cc: Akio Takebe <takebe_akio@jp.fujitsu.com>
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Preparation for paravirtualization of hand written assembly code.
They are paravirtualized by single source code and compiled multi times.
To tell those files for target (including native), add one defines.
Cc: "Dong, Eddie" <eddie.dong@intel.com>
Cc: Keith Owens <kaos@ocs.com.au>
Cc: tgingold@free.fr
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
introduce pv_cpu_ops to paravirtualize privleged instructions
which are defined by ia64 intrinsics.
make them indirect C function calls by introducing function
tables, pv_cpu_ops.
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch adds a setup hook in the very early boot sequence
before start_kernel() to initialize paravirtualization stuff.
The hook will be set by each pv loader code or by using multi entry point.
Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
introduce pv_info which describes some randome info about
underlying execution environment.
Cc: Jes Sorensen <jes@sgi.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
__local_irq_save() and local_save_flags() are used to mask interruptions.
They read all psr bits that requres whole bit emulation.
On the other hand, reading only psr.i, the single bit, can be virtualized
cheaply.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
make kernel paravirtualization friendly by introducing
ia64_set_rr0_to_rr4().
ia64/Xen will replace setting rr[0-4] with single hypercall later.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Move the LOAD_OFFSET definition from vmlinux.lds.S into system.h.
On paravirtualized environments, it is necessary to detect the
execution environment. One of the solutions is the multi entry point.
The multi entry point allows a boot loader to start the kernel execution
from the entry point which is different from the ELF entry point.
The non standard entry point will defined as the specialized elf note
which contains the LMA of the entry point symbol.
The constant, LOAD_OFFSET, is necessary to calculate the symbol's LMA.
Move the definition into the public header file to make it available
to the multi entry point support.
Cc: "He, Qing" <qing.he@intel.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
remove extern declaration of handle_IPI() in irq_ia64.c.
Instead, declare it in asm-ia64/smp.h.
Later handle_IPI() will be referenced from another file.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Problem: An application violating the architectural rules regarding
operation dependencies and having specific Register Stack Engine (RSE)
state at the time of the violation, may result in an illegal operation
fault and invalid RSE state. Such faults may initiate a cascade of
repeated illegal operation faults within OS interruption handlers.
The specific behavior is OS dependent.
Implication: An application causing an illegal operation fault with
specific RSE state may result in a series of illegal operation faults
and an eventual OS stack overflow condition.
Workaround: OS interruption handlers that switch to kernel backing
store implement a check for invalid RSE state to avoid the series
of illegal operation faults.
The core of the workaround is the RSE_WORKAROUND code sequence
inserted into each invocation of the SAVE_MIN_WITH_COVER and
SAVE_MIN_WITH_COVER_R19 macros. This sequence includes hard-coded
constants that depend on the number of stacked physical registers
being 96. The rest of this patch consists of code to disable this
workaround should this not be the case (with the presumption that
if a future Itanium processor increases the number of registers, it
would also remove the need for this patch).
Move the start of the RBS up to a mod32 boundary to avoid some
corner cases.
The dispatch_illegal_op_fault code outgrew the spot it was
squatting in when built with this patch and CONFIG_VIRT_CPU_ACCOUNTING=y
Move it out to the end of the ivt.
Signed-off-by: Tony Luck <tony.luck@intel.com>
There is a new #if 0 section here which is a suggested fix for the horrible
PCI hack in the existing code. Would be good if someone with a box that uses
this device could test it.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Some versions of the Virtual I/O Server on Power
return 0x99 in the non-SCSI error status field as success,
rather than 0. This fixes the ibmvscsi driver to treat this
response as success.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Some small cleanups for aperture_64.c; they should not really change
any code.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
