If an xtensa core provides an additional IRQ controller it should be
treated as a separate piece of hardware and be driven by an irqchip
driver.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
platform/hardware.h no longer supply any information for processor.h,
vectors.h, setup.c or vmlinux.lds.S, don't include it.
This header is now empty in the platforms/iss, so remove it altogether.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Drop PLATFORM_DEFAULT_MEM_START from the platform/hardware.h headers.
Provide definition of CONFIG_DEFAULT_MEM_START always, allow changing it
only in noMMU configurations when PLATFORM_WANT_DEFAULT_MEM is selected.
Change prompt and description so that it's clear that it controls
PAGE_OFFSET and PHYS_OFFSET.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Now that noMMU cache attributes are set up separately drop no longer
used macro PLATFORM_DEFAULT_MEM_SIZE and config symbol
CONFIG_DEFAULT_MEM_SIZE used for setting it.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Commit 0bbf47eab4 ("ia64: use asm-generic/io.h") results in a BUG
while booting ia64. This is because asm-generic/io.h defines
PCI_IOBASE, which results in the function acpi_pci_root_remap_iospace()
doing a lot of unnecessary (and wrong) things.
I'd suggested an #if !CONFIG_IA64 in the functon, but Arnd suggested
keeping the fix inside the arch/ia64 tree.
Fixes: 0bbf47eab4 ("ia64: use asm-generic/io.h")
Suggested-by: Arnd Bergman <arnd@arndb.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When thermal zone is in passive mode, disabling its mode from
sysfs is NOT taking effect at all, it is still polling the
temperature of the disabled thermal zone and handling all thermal
trips, it makes user confused. The disabling operation should
disable the thermal zone behavior completely, for both active and
passive mode, this patch clears the passive_delay when thermal
zone is disabled and restores it when it is enabled.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Commit 7b25b9cb0d ("x86/xen/time: Initialize pv xen time in
init_hypervisor_platform()") moved the mapping of the shared info area
before pagetable_init(). This breaks booting as 32-bit PV guest as the
use of set_fixmap isn't possible at this time on 32-bit.
This can be worked around by populating the needed PMD on 32-bit
kernel earlier.
In order not to reimplement populate_extra_pte() using extend_brk()
for allocating new page tables extend alloc_low_pages() to do that in
case the early page table pool is not yet available.
Fixes: 7b25b9cb0d ("x86/xen/time: Initialize pv xen time in init_hypervisor_platform()")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Remove Xen hypercall functions which are used nowhere in the kernel.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
xen_auto_xlated_memory_setup() is a leftover from PVH V1. Remove it.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
This is unnecessary and triggers a warning in the hypervisor.
Often systems have more processor entries in their ACPI tables than are
actually installed/active. The ACPI_STA_DEVICE_PRESENT bit cannot be
reliably used, but the ACPI_MADT_ENABLED bit can. In order to not
introduce new functions in the main ACPI processor driver code, simply
use acpi_get_phys_id(), which does more than we need, but which checks
the MADT enabled bit in the process. Any CPU for which we can't
determine the APIC ID is unlikely to work properly anyway, so the extra
checks done by acpi_get_phys_id() should do no harm.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
As the sequence of invocations matters, add "tty" only after "hvc" when
a VGA console is available (which is often the case for Dom0, but hardly
ever for DomU).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
This already gets done in HYPERVISOR_mca().
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Its only caller is __init, so to avoid section mismatch warnings when a
compiler decides to not inline the function marke this function so as
well. Take the opportunity and also make the function actually use its
argument: The sole caller passes in zero anyway.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
As original license mentioned, it is GPL-2.0 in SPDX.
Then, MODULE_LICENSE() should be "GPL v2" instead of "GPL".
See ${LINUX}/include/linux/module.h
"GPL" [GNU Public License v2 or later]
"GPL v2" [GNU Public License v2]
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Tomer Tayar says:
====================
qed: Misc fixes in the interface with the MFW
This patch series fixes several issues in the driver's interface with the
management FW (MFW).
v1->v2:
- Fix loop counter decrement to be pre instead of post.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Keep sending mailbox commands to the MFW when it is not responsive ends up
with a redundant amount of timeout expiries.
This patch prints the MCP status on the first command which is not
responded, and blocks the following commands.
Since the (un)load request commands might be not responded due to other
PFs, the patch also adds the option to skip the blocking upon a failure.
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The MFW manages an internal lock to prevent concurrent hardware
(de)initialization of different PFs.
This, together with the busy-waiting for the MFW's responses for commands,
might lead to a deadlock during concurrent load or unload of PFs.
This patch adds the option to sleep within the busy-waiting, and uses it
for the (un)load requests (which are not sent from an interrupt context) to
prevent the possible deadlock.
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Successive iterations of halting and resuming the management chip (MCP)
might fail, since currently the driver doesn't wait for these operations to
actually take place.
This patch prevents the driver from moving forward before the operations
are reflected in the state register.
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The MFW might be reset and re-update its shared memory.
Upon the detection of such a reset the driver rereads this memory, but it
has to wait till the data is valid.
This patch adds the missing wait for a data ready indication.
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This contains a pair of patches that together fix sys_riscv_flush_icache
on all systems:
* The first enables sys_riscv_flush_icache() for non-SMP systems.
* The second fixes a bug in our syscall header that caused
sys_riscv_flush_icache to never get generated.
There is no need to assign zero to the variable 'site' and then
perform a compound bitwise OR operation afterwards.
Make it simpler by assigning the final 'site' value directly.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
By using the managed devm_thermal_zone_of_sensor_register() we can
drop the explicit call to thermal_zone_of_sensor_unregister() in the
qoriq_tmu_remove() function, which simplifies the code a bit.
So switch to devm_thermal_zone_of_sensor_register().
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
riscv does not enable CONFIG_COMPAT in default configurations:
defconfig, allmodconfig and allnoconfig.
Remove the asm/compat.h as it does not seem to add any value to
the architecture without CONFIG_COMPAT.
Now that time compat syscalls are being reused in non CONFIG_COMPAT
modes, asm-generic/compat.h provides definitions for riscv 32 bit
mode.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: palmer@sifive.com
Cc: linux-riscv@lists.infradead.org
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This file is expected to be included multiple times in the same file in
order to allow the __SYSCALL macro to generate system call tables. With
a global include guard we end up missing __NR_riscv_flush_icache in the
syscall table, which results in icache flushes that escape the vDSO call
to not actually do anything.
The fix is to move to per-#define include guards, which allows the
system call tables to actually be populated. Thanks to Macrus Comstedt
for finding and fixing the bug!
Cc: Marcus Comstedt <marcus@mc.pp.se>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This would be necessary to make non-SMP builds work, but there is
another error in the implementation of our syscall linkage that actually
just causes sys_riscv_flush_icache to never build. I've build tested
this on allnoconfig and allnoconfig+SMP=y, as well as defconfig like
normal.
CC: Christoph Hellwig <hch@infradead.org>
CC: Guenter Roeck <linux@roeck-us.net>
In-Reply-To: <20180809055830.GA17533@infradead.org>
In-Reply-To: <20180809132612.GA31058@roeck-us.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
If the system BIOS does not supply NUMA node information to the
PCI devices, the NUMA node is selected by choosing the current
node.
This can lead to the following crash:
divide error: 0000 SMP
CPU: 0 PID: 4 Comm: kworker/0:0 Tainted: G IOE
------------ 3.10.0-693.21.1.el7.x86_64 #1
Hardware name: Intel Corporation S2600KP/S2600KP, BIOS
SE5C610.86B.01.01.0005.101720141054 10/17/2014
Workqueue: events work_for_cpu_fn
task: ffff880174480fd0 ti: ffff880174488000 task.ti: ffff880174488000
RIP: 0010: [<ffffffffc020ac69>] hfi1_dev_affinity_init+0x129/0x6a0 [hfi1]
RSP: 0018:ffff88017448bbf8 EFLAGS: 00010246
RAX: 0000000000000011 RBX: ffff88107ffba6c0 RCX: ffff88085c22e130
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880824ad0000
RBP: ffff88017448bc48 R08: 0000000000000011 R09: 0000000000000002
R10: ffff8808582b6ca0 R11: 0000000000003151 R12: ffff8808582b6ca0
R13: ffff8808582b6518 R14: ffff8808582b6010 R15: 0000000000000012
FS: 0000000000000000(0000) GS:ffff88085ec00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efc707404f0 CR3: 0000000001a02000 CR4: 00000000001607f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
hfi1_init_dd+0x14b3/0x27a0 [hfi1]
? pcie_capability_write_word+0x46/0x70
? hfi1_pcie_init+0xc0/0x200 [hfi1]
do_init_one+0x153/0x4c0 [hfi1]
? sched_clock_cpu+0x85/0xc0
init_one+0x1b5/0x260 [hfi1]
local_pci_probe+0x4a/0xb0
work_for_cpu_fn+0x1a/0x30
process_one_work+0x17f/0x440
worker_thread+0x278/0x3c0
? manage_workers.isra.24+0x2a0/0x2a0
kthread+0xd1/0xe0
? insert_kthread_work+0x40/0x40
ret_from_fork+0x77/0xb0
? insert_kthread_work+0x40/0x40
If the BIOS is not supplying NUMA information:
- set the default table count to 1 for all possible nodes
- select node 0 (instead of current NUMA) node to get consistent
performance
- generate an error indicating that the BIOS should be upgraded
Reviewed-by: Gary Leshner <gary.s.leshner@intel.com>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
In preparation of enabling -Wimplicit-fallthrough, mark switch cases which
fall through.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@infradead.org>
Link: https://lkml.kernel.org/r/20180816172124.GA2407@embeddedor.com
Use clear_mce_nospec() to restore WB mode for the kernel linear mapping
of a pmem page that was marked 'HWPoison'. A page with 'HWPoison' set
has also been marked UC in PAT (page attribute table) via
set_mce_nospec() to prevent speculative retrievals of poison.
The 'HWPoison' flag is only cleared when overwriting an entire page.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Currently memory_failure() returns zero if the error was handled. On
that result mce_unmap_kpfn() is called to zap the page out of the kernel
linear mapping to prevent speculative fetches of potentially poisoned
memory. However, in the case of dax mapped devmap pages the page may be
in active permanent use by the device driver, so it cannot be unmapped
from the kernel.
Instead of marking the page not present, marking the page UC should
be sufficient for preventing poison from being pre-fetched into the
cache. Convert mce_unmap_pfn() to set_mce_nospec() remapping the page as
UC, to hide it from speculative accesses.
Given that that persistent memory errors can be cleared by the driver,
include a facility to restore the page to cacheable operation,
clear_mce_nospec().
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: <linux-edac@vger.kernel.org>
Cc: <x86@kernel.org>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
In preparation for using set_memory_uc() instead set_memory_np() for
isolating poison from speculation, teach the memtype code to sanitize
physical addresses vs __PHYSICAL_MASK.
The motivation for using set_memory_uc() for this case is to allow
ongoing access to persistent memory pages via the pmem-driver +
memcpy_mcsafe() until the poison is repaired.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: <linux-edac@vger.kernel.org>
Cc: <x86@kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
On 32bit PAE kernels on 64bit hardware with enough physical bits,
l1tf_pfn_limit() will overflow unsigned long. This in turn affects
max_swapfile_size() and can lead to swapon returning -EINVAL. This has been
observed in a 32bit guest with 42 bits physical address size, where
max_swapfile_size() overflows exactly to 1 << 32, thus zero, and produces
the following warning to dmesg:
[ 6.396845] Truncating oversized swap area, only using 0k out of 2047996k
Fix this by using unsigned long long instead.
Fixes: 17dbca1193 ("x86/speculation/l1tf: Add sysfs reporting for l1tf")
Fixes: 377eeaa8e1 ("x86/speculation/l1tf: Limit swap file size to MAX_PA/2")
Reported-by: Dominique Leuenberger <dimstar@suse.de>
Reported-by: Adrian Schroeter <adrian@suse.de>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180820095835.5298-1-vbabka@suse.cz
The consolidation of the start_thread() functions removed the export
unintentionally. This breaks binfmt handlers built as a module.
Add it back.
Fixes: e634d8fc79 ("x86-64: merge the standard and compat start_thread() functions")
Signed-off-by: Rian Hunter <rian@alum.mit.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Dmitry Safonov <dima@arista.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180819230854.7275-1-rian@alum.mit.edu
Without linux/irq.h, there is no declaration of notifier_block, leading to
a build warning:
In file included from arch/x86/kernel/cpu/mcheck/threshold.c:10:
arch/x86/include/asm/mce.h:151:46: error: 'struct notifier_block' declared inside parameter list will not be visible outside of this definition or declaration [-Werror]
It's sufficient to declare the struct tag here, which avoids pulling in
more header files.
Fixes: 447ae31667 ("x86: Don't include linux/irq.h from asm/hardirq.h")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Nicolai Stange <nstange@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20180817100156.3009043-1-arnd@arndb.de
Currently, if the vDSO ends up containing an indirect branch or
call, GCC will emit the "external thunk" style of retpoline, and it
will fail to link.
Fix it by building the vDSO with inline retpoline thunks.
I haven't seen any reports of this triggering on an unpatched
kernel.
Fixes: commit 76b043848f ("x86/retpoline: Add initial retpoline support")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Matt Rickard <matt@softrans.com.au>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jason Vas Dias <jason.vas.dias@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/c76538cd3afbe19c6246c2d1715bc6a60bd63985.1534448381.git.luto@kernel.org
Commit efda1b5d87 ("acpi, nfit, libnvdimm: fix / harden ars_status output length handling")
Introduced additional hardening for ambiguity in the ACPI spec for
ars_status output sizing. However, it had a couple of cases mixed up.
Where it should have been checking for (and returning) "out_field[1] -
4" it was using "out_field[1] - 8" and vice versa.
This caused a four byte discrepancy in the buffer size passed on to
the command handler, and in some cases, this caused memory corruption
like:
./daxdev-errors.sh: line 76: 24104 Aborted (core dumped) ./daxdev-errors $busdev $region
malloc(): memory corruption
Program received signal SIGABRT, Aborted.
[...]
#5 0x00007ffff7865a2e in calloc () from /lib64/libc.so.6
#6 0x00007ffff7bc2970 in ndctl_bus_cmd_new_ars_status (ars_cap=ars_cap@entry=0x6153b0) at ars.c:136
#7 0x0000000000401644 in check_ars_status (check=0x7fffffffdeb0, bus=0x604c20) at daxdev-errors.c:144
#8 test_daxdev_clear_error (region_name=<optimized out>, bus_name=<optimized out>)
at daxdev-errors.c:332
Cc: <stable@vger.kernel.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Lukasz Dorau <lukasz.dorau@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Fixes: efda1b5d87 ("acpi, nfit, libnvdimm: fix / harden ars_status output length handling")
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-of-by: Dave Jiang <dave.jiang@intel.com>
The current AP bus, AP devices and AP device drivers implementation
uses a clearly defined mapping for binding AP devices to AP device
drivers. So for example a CEX6C queue will always be bound to the
cex4queue device driver.
The Linux Device Driver model has no sensitivity for more than one
device driver eligible for one device type. If there exist more than
one drivers matching to the device type, simple all drivers are tried
consecutively. There is no way to determine and influence the probing
order of the drivers.
With KVM there is a need to provide additional device drivers matching
to the very same type of AP devices. With a simple implementation the
KVM drivers run in competition to the regular drivers. Whichever
'wins' a device depends on build order and implementation details
within the common Linux Device Driver Model and is not
deterministic. However, a userspace process could figure out which
device should be bound to which driver and sort out the correct
binding by manipulating attributes in the sysfs.
If for security reasons a AP device must not get bound to the 'wrong'
device driver the sorting out has to be done within the Linux kernel
by the AP bus code. This patch modifies the behavior of the AP bus
for probing drivers for devices in a way that two sets of drivers are
usable. Two new bitmasks 'apmask' and 'aqmask' are used to mark a
subset of the APQN range for 'usable by the ap bus and the default
drivers' or 'not usable by the default drivers and thus available for
alternate drivers like vfio-xxx'. So an APQN which is addressed by
this masking only the default drivers will be probed. In contrary an
APQN which is not addressed by the masks will never be probed and
bound to default drivers but onny to alternate drivers.
Eventually the two masks give a way to divide the range of APQNs into
two pools: one pool of APQNs used by the AP bus and the default
drivers and thus via zcrypt drivers available to the userspace of the
system. And another pool where no zcrypt drivers are bound to and
which can be used by alternate drivers (like vfio-xxx) for their
needs. This division is hot-plug save and makes sure a APQN assigned
to an alternate driver is at no time somehow exploitable by the wrong
party.
The two masks are located in sysfs at /sys/bus/ap/apmask and
/sys/bus/ap/aqmask. The mask syntax is exactly the same as the
already existing mask attributes in the /sys/bus/ap directory (for
example ap_usage_domain_mask and ap_control_domain_mask).
By default all APQNs belong to the ap bus and the default drivers:
cat /sys/bus/ap/apmask
0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
cat /sys/bus/ap/aqmask
0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
The masks can be changed at boot time with the kernel command line
like this:
... ap.apmask=0xffff ap.aqmask=0x40
This would give these two pools:
default drivers pool: adapter 0 - 15, domain 1
alternate drivers pool: adapter 0 - 15, all but domain 1
adapter 16-255, all domains
The sysfs attributes for this two masks are writeable and an
administrator is able to reconfigure the assignements on the fly by
writing new mask values into. With changing the mask(s) a revision of
the existing queue to driver bindings is done. So all APQNs which are
bound to the 'wrong' driver are reprobed via kernel function
device_reprobe() and thus the new correct driver will be assigned with
respect of the changed apmask and aqmask bits.
The mask values are bitmaps in big endian order starting with bit 0.
So adapter number 0 is the leftmost bit, mask is 0x8000... The sysfs
attributes accept 2 different formats:
- Absolute hex string starting with 0x like "0x12345678" does set
the mask starting from left to right. If the given string is shorter
than the mask it is padded with 0s on the right. If the string is
longer than the mask an error comes back (EINVAL).
- '+' or '-' followed by a numerical value. Valid examples are "+1",
"-13", "+0x41", "-0xff" and even "+0" and "-0". Only the addressed
bit in the mask is switched on ('+') or off ('-').
This patch will also be the base for an upcoming extension to the
zcrypt drivers to be able to provide additional zcrypt device nodes
with filtering based on ap and aq masks.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
