Commit 71054d8841 ("x86, hpet: Introduce x86_msi_ops.setup_hpet_msi")
introduced x86_msi_ops.setup_hpet_msi to setup hpet MSI irq
when irq remapping enabled. This caused a regression of
hpet MSI irq remapping.
Original code flow before commit 71054d8841:
hpet_setup_msi_irq()
arch_setup_hpet_msi()
setup_hpet_msi_remapped()
remap_ops->setup_hpet_msi()
alloc_irte()
msi_compose_msg()
hpet_msi_write()
...
Current code flow after commit 71054d8841:
hpet_setup_msi_irq()
x86_msi.setup_hpet_msi()
setup_hpet_msi_remapped()
intel_setup_hpet_msi()
alloc_irte()
Currently, we only call alloc_irte() for hpet MSI, but
do not composed and wrote its msg...
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Don't store the SIRTP request bit in the register state. It will
otherwise become sticky and could request an Interrupt Remap Table
Pointer update on each command register write.
Found while starting to emulate IR in QEMU, not by observing problems on
real hardware.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
VT-d code currently makes use of pci_find_upstream_pcie_bridge() in
order to find the topology based alias of a device. This function has
a few problems. First, it doesn't check the entire alias path of the
device to the root bus, therefore if a PCIe device is masked upstream,
the wrong result is produced. Also, it's known to get confused and
give up when it crosses a bridge from a conventional PCI bus to a PCIe
bus that lacks a PCIe capability. The PCI-core provided DMA alias
support solves both of these problems and additionally adds support
for DMA function quirks allowing VT-d to work with devices like
Marvell and Ricoh with known broken requester IDs.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Introduce a global rwsem dmar_global_lock, which will be used to
protect DMAR related global data structures from DMAR/PCI/memory
device hotplug operations in process context.
DMA and interrupt remapping related data structures are read most,
and only change when memory/PCI/DMAR hotplug event happens.
So a global rwsem solution is adopted for balance between simplicity
and performance.
For interrupt remapping driver, function intel_irq_remapping_supported(),
dmar_table_init(), intel_enable_irq_remapping(), disable_irq_remapping(),
reenable_irq_remapping() and enable_drhd_fault_handling() etc
are called during booting, suspending and resuming with interrupt
disabled, so no need to take the global lock.
For interrupt remapping entry allocation, the locking model is:
down_read(&dmar_global_lock);
/* Find corresponding iommu */
iommu = map_hpet_to_ir(id);
if (iommu)
/*
* Allocate remapping entry and mark entry busy,
* the IOMMU won't be hot-removed until the
* allocated entry has been released.
*/
index = alloc_irte(iommu, irq, 1);
up_read(&dmar_global_lock);
For DMA remmaping driver, we only uses the dmar_global_lock rwsem to
protect functions which are only called in process context. For any
function which may be called in interrupt context, we will use RCU
to protect them in following patches.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
A few patches have been queued up for this merge window:
* Improvements for the ARM-SMMU driver
(IOMMU_EXEC support, IOMMU group support)
* Updates and fixes for the shmobile IOMMU driver
* Various fixes to generic IOMMU code and the
Intel IOMMU driver
* Some cleanups in IOMMU drivers (dev_is_pci() usage)
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Merge tag 'iommu-updates-v3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU Updates from Joerg Roedel:
"A few patches have been queued up for this merge window:
- improvements for the ARM-SMMU driver (IOMMU_EXEC support, IOMMU
group support)
- updates and fixes for the shmobile IOMMU driver
- various fixes to generic IOMMU code and the Intel IOMMU driver
- some cleanups in IOMMU drivers (dev_is_pci() usage)"
* tag 'iommu-updates-v3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (36 commits)
iommu/vt-d: Fix signedness bug in alloc_irte()
iommu/vt-d: free all resources if failed to initialize DMARs
iommu/vt-d, trivial: clean sparse warnings
iommu/vt-d: fix wrong return value of dmar_table_init()
iommu/vt-d: release invalidation queue when destroying IOMMU unit
iommu/vt-d: fix access after free issue in function free_dmar_iommu()
iommu/vt-d: keep shared resources when failed to initialize iommu devices
iommu/vt-d: fix invalid memory access when freeing DMAR irq
iommu/vt-d, trivial: simplify code with existing macros
iommu/vt-d, trivial: use defined macro instead of hardcoding
iommu/vt-d: mark internal functions as static
iommu/vt-d, trivial: clean up unused code
iommu/vt-d, trivial: check suitable flag in function detect_intel_iommu()
iommu/vt-d, trivial: print correct domain id of static identity domain
iommu/vt-d, trivial: refine support of 64bit guest address
iommu/vt-d: fix resource leakage on error recovery path in iommu_init_domains()
iommu/vt-d: fix a race window in allocating domain ID for virtual machines
iommu/vt-d: fix PCI device reference leakage on error recovery path
drm/msm: Fix link error with !MSM_IOMMU
iommu/vt-d: use dedicated bitmap to track remapping entry allocation status
...
"index" needs to be signed for the error handling to work. I deleted a
little bit of obsolete cruft related to "index" and "start_index" as
well.
Fixes: 360eb3c568 ('iommu/vt-d: use dedicated bitmap to track remapping entry allocation status')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Simplify vt-d related code with existing macros and introduce a new
macro for_each_active_drhd_unit() to enumerate all active DRHD unit.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Use defined macro instead of hardcoding in function set_ioapic_sid()
for readability.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Functions alloc_iommu() and parse_ioapics_under_ir()
are only used internally, so mark them as static.
[Joerg: Made detect_intel_iommu() non-static again for IA64]
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Flag irq_remapping_enabled is only set by intel_enable_irq_remapping(),
which is called after detect_intel_iommu(). So moving pr_info() from
detect_intel_iommu() to intel_enable_irq_remapping(), which also
slightly simplifies implementation.
Reviewed-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Currently Intel interrupt remapping drivers uses the "present" flag bit
in remapping entry to track whether an entry is allocated or not.
It works as follow:
1) allocate a remapping entry and set its "present" flag bit to 1
2) compose other fields for the entry
3) update the remapping entry with the composed value
The remapping hardware may access the entry between step 1 and step 3,
which then observers an entry with the "present" flag set but random
values in all other fields.
This patch introduces a dedicated bitmap to track remapping entry
allocation status instead of sharing the "present" flag with hardware,
thus eliminate the race window. It also simplifies the implementation.
Tested-and-reviewed-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Mark functions int get_irte() and ir_dev_scope_init() as static in
intel_irq_remapping.c because they are not used outside this file.
This eliminates the following warnings in intel_irq_remapping.c:
drivers/iommu/intel_irq_remapping.c:49:5: warning: no previous prototype for ‘get_irte’ [-Wmissing-prototypes]
drivers/iommu/intel_irq_remapping.c:810:12: warning: no previous prototype for ‘ir_dev_scope_init’ [-Wmissing-prototypes]
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Replace direct inclusions of <acpi/acpi.h>, <acpi/acpi_bus.h> and
<acpi/acpi_drivers.h>, which are incorrect, with <linux/acpi.h>
inclusions and remove some inclusions of those files that aren't
necessary.
First of all, <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h>
should not be included directly from any files that are built for
CONFIG_ACPI unset, because that generally leads to build warnings about
undefined symbols in !CONFIG_ACPI builds. For CONFIG_ACPI set,
<linux/acpi.h> includes those files and for CONFIG_ACPI unset it
provides stub ACPI symbols to be used in that case.
Second, there are ordering dependencies between those files that always
have to be met. Namely, it is required that <acpi/acpi_bus.h> be included
prior to <acpi/acpi_drivers.h> so that the acpi_pci_root declarations the
latter depends on are always there. And <acpi/acpi.h> which provides
basic ACPICA type declarations should always be included prior to any other
ACPI headers in CONFIG_ACPI builds. That also is taken care of including
<linux/acpi.h> as appropriate.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci stuff)
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> (Xen stuff)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This time the updates contain:
* Tracepoints for certain IOMMU-API functions to make
their use easier to debug
* A tracepoint for IOMMU page faults to make it easier
to get them in user space
* Updates and fixes for the new ARM SMMU driver after
the first hardware showed up
* Various other fixes and cleanups in other IOMMU drivers
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Merge tag 'iommu-updates-v3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:
"This time the updates contain:
- Tracepoints for certain IOMMU-API functions to make their use
easier to debug
- A tracepoint for IOMMU page faults to make it easier to get them in
user space
- Updates and fixes for the new ARM SMMU driver after the first
hardware showed up
- Various other fixes and cleanups in other IOMMU drivers"
* tag 'iommu-updates-v3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (26 commits)
iommu/shmobile: Enable the driver on all ARM platforms
iommu/tegra-smmu: Staticize tegra_smmu_pm_ops
iommu/tegra-gart: Staticize tegra_gart_pm_ops
iommu/vt-d: Use list_for_each_entry_safe() for dmar_domain->devices traversal
iommu/vt-d: Use for_each_drhd_unit() instead of list_for_each_entry()
iommu/vt-d: Fixed interaction of VFIO_IOMMU_MAP_DMA with IOMMU address limits
iommu/arm-smmu: Clear global and context bank fault status registers
iommu/arm-smmu: Print context fault information
iommu/arm-smmu: Check for num_context_irqs > 0 to avoid divide by zero exception
iommu/arm-smmu: Refine check for proper size of mapped region
iommu/arm-smmu: Switch to subsys_initcall for driver registration
iommu/arm-smmu: use relaxed accessors where possible
iommu/arm-smmu: replace devm_request_and_ioremap by devm_ioremap_resource
iommu: Remove stack trace from broken irq remapping warning
iommu: Change iommu driver to call io_page_fault trace event
iommu: Add iommu_error class event to iommu trace
iommu/tegra: gart: cleanup devm_* functions usage
iommu/tegra: Print phys_addr_t using %pa
iommu: No need to pass '0x' when '%pa' is used
iommu: Change iommu driver to call unmap trace event
...
This patch updates DMAR table header definitions as such enhancement
has been made in ACPICA upstream already. It ports that change to
the Linux source to reduce source code differences between Linux and
ACPICA upstream.
Build test done on x86-64 machine with the following configs enabled:
CONFIG_DMAR_TABLE
CONFIG_IRQ_REMAP
CONFIG_INTEL_IOMMU
This patch does not affect the generation of the Linux kernel binary.
[rjw: Changelog]
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The warning for the irq remapping broken check in intel_irq_remapping.c is
pretty pointless. We need the warning, but we know where its comming from, the
stack trace will always be the same, and it needlessly triggers things like
Abrt. This changes the warning to just print a text warning about BIOS being
broken, without the stack trace, then sets the appropriate taint bit. Since we
automatically disable irq remapping, theres no need to contiue making Abrt jump
at this problem
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Joerg Roedel <joro@8bytes.org>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
This triggers on a MacBook Pro.
See https://bugzilla.redhat.com/show_bug.cgi?id=948262 for
the problem report.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
A few years back intel published a spec update:
http://www.intel.com/content/dam/doc/specification-update/5520-and-5500-chipset-ioh-specification-update.pdf
For the 5520 and 5500 chipsets which contained an errata (specificially errata
53), which noted that these chipsets can't properly do interrupt remapping, and
as a result the recommend that interrupt remapping be disabled in bios. While
many vendors have a bios update to do exactly that, not all do, and of course
not all users update their bios to a level that corrects the problem. As a
result, occasionally interrupts can arrive at a cpu even after affinity for that
interrupt has be moved, leading to lost or spurrious interrupts (usually
characterized by the message:
kernel: do_IRQ: 7.71 No irq handler for vector (irq -1)
There have been several incidents recently of people seeing this error, and
investigation has shown that they have system for which their BIOS level is such
that this feature was not properly turned off. As such, it would be good to
give them a reminder that their systems are vulnurable to this problem. For
details of those that reported the problem, please see:
https://bugzilla.redhat.com/show_bug.cgi?id=887006
[ Joerg: Removed CONFIG_IRQ_REMAP ifdef from early-quirks.c ]
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Prarit Bhargava <prarit@redhat.com>
CC: Don Zickus <dzickus@redhat.com>
CC: Don Dutile <ddutile@redhat.com>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Asit Mallick <asit.k.mallick@intel.com>
CC: David Woodhouse <dwmw2@infradead.org>
CC: linux-pci@vger.kernel.org
CC: Joerg Roedel <joro@8bytes.org>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: Arkadiusz Miśkiewicz <arekm@maven.pl>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Current kernels print this on my Dell server:
------------[ cut here ]------------
WARNING: at drivers/iommu/intel_irq_remapping.c:542
intel_enable_irq_remapping+0x7b/0x27e()
Hardware name: PowerEdge R620
Your BIOS is broken and requested that x2apic be disabled
This will leave your machine vulnerable to irq-injection attacks
Use 'intremap=no_x2apic_optout' to override BIOS request
[...]
Enabled IRQ remapping in xapic mode
x2apic not enabled, IRQ remapping is in xapic mode
This is inconsistent with itself -- interrupt remapping is *on*.
Fix the mess by making the warnings say what they mean and my
making sure that compatibility format interrupts (the dangerous
ones) are disabled if x2apic is present regardless of BIOS
settings.
With this patch applied, the output is:
Your BIOS is broken and requested that x2apic be disabled.
This will slightly decrease performance.
Use 'intremap=no_x2apic_optout' to override BIOS request.
Enabled IRQ remapping in xapic mode
x2apic not enabled, IRQ remapping is in xapic mode
This should make us as or more secure than we are now and
replace a rather scary warning with a much less scary warning on
silly but functional systems.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Link: http://lkml.kernel.org/r/2011b943a886fd7c46079eb10bc24fc130587503.1359759303.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Move all the code to either to the header file
asm/irq_remapping.h or to drivers/iommu/.
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Acked-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This call-back is used to dump IO-APIC entries for debugging
purposes into the kernel log. VT-d needs a special routine
for this and will overwrite the default.
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Acked-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The ACPI tables in the Macbook Air 5,1 define a single IOAPIC with id 2,
but the only remapping unit described in the DMAR table matches id 0.
Interrupt remapping fails as a result, and the kernel panics with the
message "timer doesn't work through Interrupt-remapped IO-APIC."
To fix this, check each IOAPIC for a corresponding IOMMU. If an IOMMU is
not found, do not allow IRQ remapping to be enabled.
v2: Move check to parse_ioapics_under_ir(), raise log level to KERN_ERR,
and add FW_BUG to the log message
v3: Skip check if IOMMU doesn't support interrupt remapping and remove
existing check that the IOMMU count equals the IOAPIC count
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Move the ->irq_set_affinity() routines out of the #ifdef CONFIG_SMP
sections and use config_enabled(CONFIG_SMP) checks inside those
routines. Thus making those routines simple null stubs for
!CONFIG_SMP and retaining those routines with no additional
runtime overhead for CONFIG_SMP kernels.
Cleans up the ifdef CONFIG_SMP in and around routines related to
irq_set_affinity in io_apic and irq_remapping subsystems.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: torvalds@linux-foundation.org
Cc: joerg.roedel@amd.com
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/1339723729.3475.63.camel@sbsiddha-desk.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is an extra semicolon here so the pr_err() message is
printed when it is not intended.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: Alexander Gordeev <agordeev@redhat.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Link: http://lkml.kernel.org/r/20120612162633.GA11077@elgon.mountain
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Current cpu_mask_to_apicid() and cpu_mask_to_apicid_and()
implementations have few shortcomings:
1. A value returned by cpu_mask_to_apicid() is written to
hardware registers unconditionally. Should BAD_APICID get ever
returned it will be written to a hardware too. But the value of
BAD_APICID is not universal across all hardware in all modes and
might cause unexpected results, i.e. interrupts might get routed
to CPUs that are not configured to receive it.
2. Because the value of BAD_APICID is not universal it is
counter- intuitive to return it for a hardware where it does not
make sense (i.e. x2apic).
3. cpu_mask_to_apicid_and() operation is thought as an
complement to cpu_mask_to_apicid() that only applies a AND mask
on top of a cpumask being passed. Yet, as consequence of 18374d8
commit the two operations are inconsistent in that of:
cpu_mask_to_apicid() should not get a offline CPU with the cpumask
cpu_mask_to_apicid_and() should not fail and return BAD_APICID
These limitations are impossible to realize just from looking at
the operations prototypes.
Most of these shortcomings are resolved by returning a error
code instead of BAD_APICID. As the result, faults are reported
back early rather than possibilities to cause a unexpected
behaviour exist (in case of [1]).
The only exception is setup_timer_IRQ0_pin() routine. Although
obviously controversial to this fix, its existing behaviour is
preserved to not break the fragile check_timer() and would
better addressed in a separate fix.
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/20120607131559.GF4759@dhcp-26-207.brq.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Make the file names consistent with the naming conventions of irq subsystem.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
