We allocate only the first level of multilevel TCE tables for KVM
already (alloc_userspace_copy==true), and the rest is allocated on demand.
This is not enabled though for bare metal.
This removes the KVM limitation (implicit, via the alloc_userspace_copy
parameter) and always allocates just the first level. The on-demand
allocation of missing levels is already implemented.
As from now on DMA map might happen with disabled interrupts, this
allocates TCEs with GFP_ATOMIC; otherwise lockdep reports errors 1].
In practice just a single page is allocated there so chances for failure
are quite low.
To save time when creating a new clean table, this skips non-allocated
indirect TCE entries in pnv_tce_free just like we already do in
the VFIO IOMMU TCE driver.
This changes the default level number from 1 to 2 to reduce the amount
of memory required for the default 32bit DMA window at the boot time.
The default window size is up to 2GB which requires 4MB of TCEs which is
unlikely to be used entirely or at all as most devices these days are
64bit capable so by switching to 2 levels by default we save 4032KB of
RAM per a device.
While at this, add __GFP_NOWARN to alloc_pages_node() as the userspace
can trigger this path via VFIO, see the failure and try creating a table
again with different parameters which might succeed.
[1]:
===
BUG: sleeping function called from invalid context at mm/page_alloc.c:4596
in_atomic(): 1, irqs_disabled(): 1, pid: 1038, name: scsi_eh_1
2 locks held by scsi_eh_1/1038:
#0: 000000005efd659a (&host->eh_mutex){+.+.}, at: ata_eh_acquire+0x34/0x80
#1: 0000000006cf56a6 (&(&host->lock)->rlock){....}, at: ata_exec_internal_sg+0xb0/0x5c0
irq event stamp: 500
hardirqs last enabled at (499): [<c000000000cb8a74>] _raw_spin_unlock_irqrestore+0x94/0xd0
hardirqs last disabled at (500): [<c000000000cb85c4>] _raw_spin_lock_irqsave+0x44/0x120
softirqs last enabled at (0): [<c000000000101120>] copy_process.isra.4.part.5+0x640/0x1a80
softirqs last disabled at (0): [<0000000000000000>] 0x0
CPU: 73 PID: 1038 Comm: scsi_eh_1 Not tainted 5.2.0-rc6-le_nv2_aikATfstn1-p1 #634
Call Trace:
[c000003d064cef50] [c000000000c8e6c4] dump_stack+0xe8/0x164 (unreliable)
[c000003d064cefa0] [c00000000014ed78] ___might_sleep+0x2f8/0x310
[c000003d064cf020] [c0000000003ca084] __alloc_pages_nodemask+0x2a4/0x1560
[c000003d064cf220] [c0000000000c2530] pnv_alloc_tce_level.isra.0+0x90/0x130
[c000003d064cf290] [c0000000000c2888] pnv_tce+0x128/0x3b0
[c000003d064cf360] [c0000000000c2c00] pnv_tce_build+0xb0/0xf0
[c000003d064cf3c0] [c0000000000bbd9c] pnv_ioda2_tce_build+0x3c/0xb0
[c000003d064cf400] [c00000000004cfe0] ppc_iommu_map_sg+0x210/0x550
[c000003d064cf510] [c00000000004b7a4] dma_iommu_map_sg+0x74/0xb0
[c000003d064cf530] [c000000000863944] ata_qc_issue+0x134/0x470
[c000003d064cf5b0] [c000000000863ec4] ata_exec_internal_sg+0x244/0x5c0
[c000003d064cf700] [c0000000008642d0] ata_exec_internal+0x90/0xe0
[c000003d064cf780] [c0000000008650ac] ata_dev_read_id+0x2ec/0x640
[c000003d064cf8d0] [c000000000878e28] ata_eh_recover+0x948/0x16d0
[c000003d064cfa10] [c00000000087d760] sata_pmp_error_handler+0x480/0xbf0
[c000003d064cfbc0] [c000000000884624] ahci_error_handler+0x74/0xe0
[c000003d064cfbf0] [c000000000879fa8] ata_scsi_port_error_handler+0x2d8/0x7c0
[c000003d064cfca0] [c00000000087a544] ata_scsi_error+0xb4/0x100
[c000003d064cfd00] [c000000000802450] scsi_error_handler+0x120/0x510
[c000003d064cfdb0] [c000000000140c48] kthread+0x1b8/0x1c0
[c000003d064cfe20] [c00000000000bd8c] ret_from_kernel_thread+0x5c/0x70
ata1: SATA link up 6.0 Gbps (SStatus 133 SControl 300)
irq event stamp: 2305
========================================================
hardirqs last enabled at (2305): [<c00000000000e4c8>] fast_exc_return_irq+0x28/0x34
hardirqs last disabled at (2303): [<c000000000cb9fd0>] __do_softirq+0x4a0/0x654
WARNING: possible irq lock inversion dependency detected
5.2.0-rc6-le_nv2_aikATfstn1-p1 #634 Tainted: G W
softirqs last enabled at (2304): [<c000000000cba054>] __do_softirq+0x524/0x654
softirqs last disabled at (2297): [<c00000000010f278>] irq_exit+0x128/0x180
--------------------------------------------------------
swapper/0/0 just changed the state of lock:
0000000006cf56a6 (&(&host->lock)->rlock){-...}, at: ahci_single_level_irq_intr+0xac/0x120
but this lock took another, HARDIRQ-unsafe lock in the past:
(fs_reclaim){+.+.}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
local_irq_disable();
lock(&(&host->lock)->rlock);
lock(fs_reclaim);
<Interrupt>
lock(&(&host->lock)->rlock);
*** DEADLOCK ***
no locks held by swapper/0/0.
the shortest dependencies between 2nd lock and 1st lock:
-> (fs_reclaim){+.+.} ops: 167579 {
HARDIRQ-ON-W at:
lock_acquire+0xf8/0x2a0
fs_reclaim_acquire.part.23+0x44/0x60
kmem_cache_alloc_node_trace+0x80/0x590
alloc_desc+0x64/0x270
__irq_alloc_descs+0x2e4/0x3a0
irq_domain_alloc_descs+0xb0/0x150
irq_create_mapping+0x168/0x2c0
xics_smp_probe+0x2c/0x98
pnv_smp_probe+0x40/0x9c
smp_prepare_cpus+0x524/0x6c4
kernel_init_freeable+0x1b4/0x650
kernel_init+0x2c/0x148
ret_from_kernel_thread+0x5c/0x70
SOFTIRQ-ON-W at:
lock_acquire+0xf8/0x2a0
fs_reclaim_acquire.part.23+0x44/0x60
kmem_cache_alloc_node_trace+0x80/0x590
alloc_desc+0x64/0x270
__irq_alloc_descs+0x2e4/0x3a0
irq_domain_alloc_descs+0xb0/0x150
irq_create_mapping+0x168/0x2c0
xics_smp_probe+0x2c/0x98
pnv_smp_probe+0x40/0x9c
smp_prepare_cpus+0x524/0x6c4
kernel_init_freeable+0x1b4/0x650
kernel_init+0x2c/0x148
ret_from_kernel_thread+0x5c/0x70
INITIAL USE at:
lock_acquire+0xf8/0x2a0
fs_reclaim_acquire.part.23+0x44/0x60
kmem_cache_alloc_node_trace+0x80/0x590
alloc_desc+0x64/0x270
__irq_alloc_descs+0x2e4/0x3a0
irq_domain_alloc_descs+0xb0/0x150
irq_create_mapping+0x168/0x2c0
xics_smp_probe+0x2c/0x98
pnv_smp_probe+0x40/0x9c
smp_prepare_cpus+0x524/0x6c4
kernel_init_freeable+0x1b4/0x650
kernel_init+0x2c/0x148
ret_from_kernel_thread+0x5c/0x70
}
===
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190718051139.74787-4-aik@ozlabs.ru
POWER8 and newer support a bypass mode which maps all host memory to
PCI buses so an IOMMU table is not always required. However if we fail to
create such a table, the DMA setup fails and the kernel does not boot.
This skips the 32bit DMA setup check if the bypass is selected.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190718051139.74787-3-aik@ozlabs.ru
pnv_tce() returns a pointer to a TCE entry and originally a TCE table
would be pre-allocated. For the default case of 2GB window the table
needs only a single level and that is fine. However if more levels are
requested, it is possible to get a race when 2 threads want a pointer
to a TCE entry from the same page of TCEs.
This adds cmpxchg to handle the race. Note that once TCE is non-zero,
it cannot become zero again.
Fixes: a68bd1267b ("powerpc/powernv/ioda: Allocate indirect TCE levels on demand")
CC: stable@vger.kernel.org # v4.19+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190718051139.74787-2-aik@ozlabs.ru
The calls to arch_add_memory()/arch_remove_memory() are always made
with the read-side cpu_hotplug_lock acquired via memory_hotplug_begin().
On pSeries, arch_add_memory()/arch_remove_memory() eventually call
resize_hpt() which in turn calls stop_machine() which acquires the
read-side cpu_hotplug_lock again, thereby resulting in the recursive
acquisition of this lock.
In the absence of CONFIG_PROVE_LOCKING, we hadn't observed a system
lockup during a memory hotplug operation because cpus_read_lock() is a
per-cpu rwsem read, which, in the fast-path (in the absence of the
writer, which in our case is a CPU-hotplug operation) simply
increments the read_count on the semaphore. Thus a recursive read in
the fast-path doesn't cause any problems.
However, we can hit this problem in practice if there is a concurrent
CPU-Hotplug operation in progress which is waiting to acquire the
write-side of the lock. This will cause the second recursive read to
block until the writer finishes. While the writer is blocked since the
first read holds the lock. Thus both the reader as well as the writers
fail to make any progress thereby blocking both CPU-Hotplug as well as
Memory Hotplug operations.
Memory-Hotplug CPU-Hotplug
CPU 0 CPU 1
------ ------
1. down_read(cpu_hotplug_lock.rw_sem)
[memory_hotplug_begin]
2. down_write(cpu_hotplug_lock.rw_sem)
[cpu_up/cpu_down]
3. down_read(cpu_hotplug_lock.rw_sem)
[stop_machine()]
Lockdep complains as follows in these code-paths.
swapper/0/1 is trying to acquire lock:
(____ptrval____) (cpu_hotplug_lock.rw_sem){++++}, at: stop_machine+0x2c/0x60
but task is already holding lock:
(____ptrval____) (cpu_hotplug_lock.rw_sem){++++}, at: mem_hotplug_begin+0x20/0x50
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(cpu_hotplug_lock.rw_sem);
lock(cpu_hotplug_lock.rw_sem);
*** DEADLOCK ***
May be due to missing lock nesting notation
3 locks held by swapper/0/1:
#0: (____ptrval____) (&dev->mutex){....}, at: __driver_attach+0x12c/0x1b0
#1: (____ptrval____) (cpu_hotplug_lock.rw_sem){++++}, at: mem_hotplug_begin+0x20/0x50
#2: (____ptrval____) (mem_hotplug_lock.rw_sem){++++}, at: percpu_down_write+0x54/0x1a0
stack backtrace:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.0.0-rc5-58373-gbc99402235f3-dirty #166
Call Trace:
dump_stack+0xe8/0x164 (unreliable)
__lock_acquire+0x1110/0x1c70
lock_acquire+0x240/0x290
cpus_read_lock+0x64/0xf0
stop_machine+0x2c/0x60
pseries_lpar_resize_hpt+0x19c/0x2c0
resize_hpt_for_hotplug+0x70/0xd0
arch_add_memory+0x58/0xfc
devm_memremap_pages+0x5e8/0x8f0
pmem_attach_disk+0x764/0x830
nvdimm_bus_probe+0x118/0x240
really_probe+0x230/0x4b0
driver_probe_device+0x16c/0x1e0
__driver_attach+0x148/0x1b0
bus_for_each_dev+0x90/0x130
driver_attach+0x34/0x50
bus_add_driver+0x1a8/0x360
driver_register+0x108/0x170
__nd_driver_register+0xd0/0xf0
nd_pmem_driver_init+0x34/0x48
do_one_initcall+0x1e0/0x45c
kernel_init_freeable+0x540/0x64c
kernel_init+0x2c/0x160
ret_from_kernel_thread+0x5c/0x68
Fix this issue by
1) Requiring all the calls to pseries_lpar_resize_hpt() be made
with cpu_hotplug_lock held.
2) In pseries_lpar_resize_hpt() invoke stop_machine_cpuslocked()
as a consequence of 1)
3) To satisfy 1), in hpt_order_set(), call mmu_hash_ops.resize_hpt()
with cpu_hotplug_lock held.
Fixes: dbcf929c00 ("powerpc/pseries: Add support for hash table resizing")
Cc: stable@vger.kernel.org # v4.11+
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1557906352-29048-1-git-send-email-ego@linux.vnet.ibm.com
Testing has revealed the existence of a race condition where a XIVE
interrupt being shut down can be in one of the XIVE interrupt queues
(of which there are up to 8 per CPU, one for each priority) at the
point where free_irq() is called. If this happens, can return an
interrupt number which has been shut down. This can lead to various
symptoms:
- irq_to_desc(irq) can be NULL. In this case, no end-of-interrupt
function gets called, resulting in the CPU's elevated interrupt
priority (numerically lowered CPPR) never gets reset. That then
means that the CPU stops processing interrupts, causing device
timeouts and other errors in various device drivers.
- The irq descriptor or related data structures can be in the process
of being freed as the interrupt code is using them. This typically
leads to crashes due to bad pointer dereferences.
This race is basically what commit 62e0468650 ("genirq: Add optional
hardware synchronization for shutdown", 2019-06-28) is intended to
fix, given a get_irqchip_state() method for the interrupt controller
being used. It works by polling the interrupt controller when an
interrupt is being freed until the controller says it is not pending.
With XIVE, the PQ bits of the interrupt source indicate the state of
the interrupt source, and in particular the P bit goes from 0 to 1 at
the point where the hardware writes an entry into the interrupt queue
that this interrupt is directed towards. Normally, the code will then
process the interrupt and do an end-of-interrupt (EOI) operation which
will reset PQ to 00 (assuming another interrupt hasn't been generated
in the meantime). However, there are situations where the code resets
P even though a queue entry exists (for example, by setting PQ to 01,
which disables the interrupt source), and also situations where the
code leaves P at 1 after removing the queue entry (for example, this
is done for escalation interrupts so they cannot fire again until
they are explicitly re-enabled).
The code already has a 'saved_p' flag for the interrupt source which
indicates that a queue entry exists, although it isn't maintained
consistently. This patch adds a 'stale_p' flag to indicate that
P has been left at 1 after processing a queue entry, and adds code
to set and clear saved_p and stale_p as necessary to maintain a
consistent indication of whether a queue entry may or may not exist.
With this, we can implement xive_get_irqchip_state() by looking at
stale_p, saved_p and the ESB PQ bits for the interrupt.
There is some additional code to handle escalation interrupts
properly; because they are enabled and disabled in KVM assembly code,
which does not have access to the xive_irq_data struct for the
escalation interrupt. Hence, stale_p may be incorrect when the
escalation interrupt is freed in kvmppc_xive_{,native_}cleanup_vcpu().
Fortunately, we can fix it up by looking at vcpu->arch.xive_esc_on,
with some careful attention to barriers in order to ensure the correct
result if xive_esc_irq() races with kvmppc_xive_cleanup_vcpu().
Finally, this adds code to make noise on the console (pr_crit and
WARN_ON(1)) if we find an interrupt queue entry for an interrupt
which does not have a descriptor. While this won't catch the race
reliably, if it does get triggered it will be an indication that
the race is occurring and needs to be debugged.
Fixes: 243e25112d ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190813100648.GE9567@blackberry
At present, when running a guest on POWER9 using HV KVM but not using
an in-kernel interrupt controller (XICS or XIVE), for example if QEMU
is run with the kernel_irqchip=off option, the guest entry code goes
ahead and tries to load the guest context into the XIVE hardware, even
though no context has been set up.
To fix this, we check that the "CAM word" is non-zero before pushing
it to the hardware. The CAM word is initialized to a non-zero value
in kvmppc_xive_connect_vcpu() and kvmppc_xive_native_connect_vcpu(),
and is now cleared in kvmppc_xive_{,native_}cleanup_vcpu.
Fixes: 5af5099385 ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.12+
Reported-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190813100100.GC9567@blackberry
Escalation interrupts are interrupts sent to the host by the XIVE
hardware when it has an interrupt to deliver to a guest VCPU but that
VCPU is not running anywhere in the system. Hence we disable the
escalation interrupt for the VCPU being run when we enter the guest
and re-enable it when the guest does an H_CEDE hypercall indicating
it is idle.
It is possible that an escalation interrupt gets generated just as we
are entering the guest. In that case the escalation interrupt may be
using a queue entry in one of the interrupt queues, and that queue
entry may not have been processed when the guest exits with an H_CEDE.
The existing entry code detects this situation and does not clear the
vcpu->arch.xive_esc_on flag as an indication that there is a pending
queue entry (if the queue entry gets processed, xive_esc_irq() will
clear the flag). There is a comment in the code saying that if the
flag is still set on H_CEDE, we have to abort the cede rather than
re-enabling the escalation interrupt, lest we end up with two
occurrences of the escalation interrupt in the interrupt queue.
However, the exit code doesn't do that; it aborts the cede in the sense
that vcpu->arch.ceded gets cleared, but it still enables the escalation
interrupt by setting the source's PQ bits to 00. Instead we need to
set the PQ bits to 10, indicating that an interrupt has been triggered.
We also need to avoid setting vcpu->arch.xive_esc_on in this case
(i.e. vcpu->arch.xive_esc_on seen to be set on H_CEDE) because
xive_esc_irq() will run at some point and clear it, and if we race with
that we may end up with an incorrect result (i.e. xive_esc_on set when
the escalation interrupt has just been handled).
It is extremely unlikely that having two queue entries would cause
observable problems; theoretically it could cause queue overflow, but
the CPU would have to have thousands of interrupts targetted to it for
that to be possible. However, this fix will also make it possible to
determine accurately whether there is an unhandled escalation
interrupt in the queue, which will be needed by the following patch.
Fixes: 9b9b13a6d1 ("KVM: PPC: Book3S HV: Keep XIVE escalation interrupt masked unless ceded")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190813100349.GD9567@blackberry
When a vCPU is brought done, the XIVE VP (Virtual Processor) is first
disabled and then the event notification queues are freed. When freeing
the queues, we check for possible escalation interrupts and free them
also.
But when a XIVE VP is disabled, the underlying XIVE ENDs also are
disabled in OPAL. When an END (Event Notification Descriptor) is
disabled, its ESB pages (ESn and ESe) are disabled and loads return all
1s. Which means that any access on the ESB page of the escalation
interrupt will return invalid values.
When an interrupt is freed, the shutdown handler computes a 'saved_p'
field from the value returned by a load in xive_do_source_set_mask().
This value is incorrect for escalation interrupts for the reason
described above.
This has no impact on Linux/KVM today because we don't make use of it
but we will introduce in future changes a xive_get_irqchip_state()
handler. This handler will use the 'saved_p' field to return the state
of an interrupt and 'saved_p' being incorrect, softlockup will occur.
Fix the vCPU cleanup sequence by first freeing the escalation interrupts
if any, then disable the XIVE VP and last free the queues.
Fixes: 90c73795af ("KVM: PPC: Book3S HV: Add a new KVM device for the XIVE native exploitation mode")
Fixes: 5af5099385 ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190806172538.5087-1-clg@kaod.org
There is no need to use GFP_ATOMIC here. GFP_KERNEL should be enough.
GFP_KERNEL is also already used for another allocation just a few lines
below.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/85d5d247ce753befd6aa63c473f7823de6520ccd.1564647619.git.christophe.jaillet@wanadoo.fr
Commit ebb9d30a6a ("powerpc/mm: any thread in one core can be the
first to setup TLB1") removed the need to know the cpu_id in
early_init_this_mmu(), but the call to smp_processor_id() which was
marked __maybe_used remained.
Since commit ed1cd6deb0 ("powerpc: Activate CONFIG_THREAD_INFO_IN_TASK")
thread_info cannot be reached before MMU is properly set up.
Drop this stale call to smp_processor_id() which makes SMP hang when
CONFIG_PREEMPT is set.
Fixes: ebb9d30a6a ("powerpc/mm: any thread in one core can be the first to setup TLB1")
Fixes: ed1cd6deb0 ("powerpc: Activate CONFIG_THREAD_INFO_IN_TASK")
Cc: stable@vger.kernel.org # v5.1+
Reported-by: Chris Packham <Chris.Packham@alliedtelesis.co.nz>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/bef479514f4c08329fa649f67735df8918bc0976.1565268248.git.christophe.leroy@c-s.fr
I noticed these nested ifs can be easily replaced by switch-cases,
which can improve readability.
Signed-off-by: Leonardo Bras <leonardo@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190801225251.17864-1-leonardo@linux.ibm.com
The comment above xive_esb_read() references magic loads from an ESB as
described xive.h. This has been inaccurate since commit 12c1f339cd
("powerpc/xive: Move definition of ESB bits") which moved the
description. Update the comment to reference the new location of the
description in xive-regs.h
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Acked-by: Stewart Smith <stewart@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190802000835.26191-1-jniethe5@gmail.com
Currently the OPAL symbol map is globally readable, which seems bad as
it contains physical addresses.
Restrict it to root.
Fixes: c8742f8512 ("powerpc/powernv: Expose OPAL firmware symbol map")
Cc: stable@vger.kernel.org # v3.19+
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190503075253.22798-1-ajd@linux.ibm.com
SCOM_DEBUGFS is really not needed for anything other than low-level
hardware debugging.
mpe: It also introduces a large and poorly documented/understood
attack surface. Although the interface is only available to root, the
kernel still aspires to restrict root to accessing hardware through
well defined interfaces, which this is not.
opal-prd uses its own interface (/dev/prd) for SCOM access, so it
doesn't need SCOM_DEBUGFS.
At some point in the future we'll introduce a debug config fragment
where this can go instead.
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190509051119.7694-5-ajd@linux.ibm.com
Once upon a time, the SCOM access code was used by the WSP platform as
well as powernv. Thus it made sense to have a generic SCOM access
interface to abstract between different platforms.
Now that it's just powernv, with no other platforms currently on the
horizon, let's rip out scom_controller and make everything much
simpler and more direct.
While we're here, fix up the comment block at the top.
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190509051119.7694-3-ajd@linux.ibm.com
Nothing is using scom_map_device() or scom_find_parent(). Remove them.
Also don't export scom_controller, there are no other users of it.
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190509051119.7694-2-ajd@linux.ibm.com
The powernv platform is the only one that directly accesses SCOMs.
Move the support code to platforms/powernv, and get rid of the
PPC_SCOM Kconfig option, as SCOM support is always selected when
compiling for powernv.
This also means that the Kconfig item for CONFIG_SCOM_DEBUGFS will
show up in menuconfig in the platform menu, rather than at the root,
which is a much better location.
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190509051119.7694-1-ajd@linux.ibm.com
These aren't used by modular code, nor should they be.
Fixes: 120496ac2d ("powerpc: Bring all threads online prior to migration/hibernation")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190718162214.5694-1-nathanl@linux.ibm.com
This reverts commit 6c5875843b.
It triggers a probable compiler bug on clang which leads to crashes.
With GCC it allows the compiler to use a more efficient register
allocation but current GCC versions never do that at any of the current
call sites, so there's no benefit.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Mark switch cases where we are expecting to fall through.
Fixes errors such as below, seen with mpc85xx_defconfig:
arch/powerpc/kernel/align.c: In function 'emulate_spe':
arch/powerpc/kernel/align.c:178:8: error: this statement may fall through
ret |= __get_user_inatomic(temp.v[3], p++);
^~
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190730141917.21817-1-mpe@ellerman.id.au
Currently, nvdimm subsystem expects the device numa node for SCM device to be
an online node. It also doesn't try to bring the device numa node online. Hence
if we use a non-online numa node as device node we hit crashes like below. This
is because we try to access uninitialized NODE_DATA in different code paths.
cpu 0x0: Vector: 300 (Data Access) at [c0000000fac53170]
pc: c0000000004bbc50: ___slab_alloc+0x120/0xca0
lr: c0000000004bc834: __slab_alloc+0x64/0xc0
sp: c0000000fac53400
msr: 8000000002009033
dar: 73e8
dsisr: 80000
current = 0xc0000000fabb6d80
paca = 0xc000000003870000 irqmask: 0x03 irq_happened: 0x01
pid = 7, comm = kworker/u16:0
Linux version 5.2.0-06234-g76bd729b2644 (kvaneesh@ltc-boston123) (gcc version 7.4.0 (Ubuntu 7.4.0-1ubuntu1~18.04.1)) #135 SMP Thu Jul 11 05:36:30 CDT 2019
enter ? for help
[link register ] c0000000004bc834 __slab_alloc+0x64/0xc0
[c0000000fac53400] c0000000fac53480 (unreliable)
[c0000000fac53500] c0000000004bc818 __slab_alloc+0x48/0xc0
[c0000000fac53560] c0000000004c30a0 __kmalloc_node_track_caller+0x3c0/0x6b0
[c0000000fac535d0] c000000000cfafe4 devm_kmalloc+0x74/0xc0
[c0000000fac53600] c000000000d69434 nd_region_activate+0x144/0x560
[c0000000fac536d0] c000000000d6b19c nd_region_probe+0x17c/0x370
[c0000000fac537b0] c000000000d6349c nvdimm_bus_probe+0x10c/0x230
[c0000000fac53840] c000000000cf3cc4 really_probe+0x254/0x4e0
[c0000000fac538d0] c000000000cf429c driver_probe_device+0x16c/0x1e0
[c0000000fac53950] c000000000cf0b44 bus_for_each_drv+0x94/0x130
[c0000000fac539b0] c000000000cf392c __device_attach+0xdc/0x200
[c0000000fac53a50] c000000000cf231c bus_probe_device+0x4c/0xf0
[c0000000fac53a90] c000000000ced268 device_add+0x528/0x810
[c0000000fac53b60] c000000000d62a58 nd_async_device_register+0x28/0xa0
[c0000000fac53bd0] c0000000001ccb8c async_run_entry_fn+0xcc/0x1f0
[c0000000fac53c50] c0000000001bcd9c process_one_work+0x46c/0x860
[c0000000fac53d20] c0000000001bd4f4 worker_thread+0x364/0x5f0
[c0000000fac53db0] c0000000001c7260 kthread+0x1b0/0x1c0
[c0000000fac53e20] c00000000000b954 ret_from_kernel_thread+0x5c/0x68
The patch tries to fix this by picking the nearest online node as the SCM node.
This does have a problem of us losing the information that SCM node is
equidistant from two other online nodes. If applications need to understand these
fine-grained details we should express then like x86 does via
/sys/devices/system/node/nodeX/accessY/initiators/
With the patch we get
# numactl -H
available: 2 nodes (0-1)
node 0 cpus:
node 0 size: 0 MB
node 0 free: 0 MB
node 1 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
node 1 size: 130865 MB
node 1 free: 129130 MB
node distances:
node 0 1
0: 10 20
1: 20 10
# cat /sys/bus/nd/devices/region0/numa_node
0
# dmesg | grep papr_scm
[ 91.332305] papr_scm ibm,persistent-memory:ibm,pmemory@44104001: Region registered with target node 2 and online node 0
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190729095128.23707-1-aneesh.kumar@linux.ibm.com
Implicit fallthrough warning was enabled globally which broke
the build. Make it explicit with a `fall through` comment.
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Reviewed-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190729055536.25591-1-santosh@fossix.org
Wire up the new clone3 syscall added in commit 7f192e3cd3 ("fork:
add clone3").
This requires a ppc_clone3 wrapper, in order to save the non-volatile
GPRs before calling into the generic syscall code. Otherwise we hit
the BUG_ON in CHECK_FULL_REGS in copy_thread().
Lightly tested using Christian's test code on a Power8 LE VM.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Christian Brauner <christian@brauner.io>
Link: https://lore.kernel.org/r/20190724140259.23554-1-mpe@ellerman.id.au
Here are some small SPDX fixes for 5.3-rc2 for things that came in
during the 5.3-rc1 merge window that we previously missed.
Only 3 small patches here:
- 2 uapi patches to resolve some SPDX tags that were not correct
- fix an invalid SPDX tag in the iomap Makefile file
All have been properly reviewed on the public mailing lists.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx
Pull SPDX fixes from Greg KH:
"Here are some small SPDX fixes for 5.3-rc2 for things that came in
during the 5.3-rc1 merge window that we previously missed.
Only three small patches here:
- two uapi patches to resolve some SPDX tags that were not correct
- fix an invalid SPDX tag in the iomap Makefile file
All have been properly reviewed on the public mailing lists"
* tag 'spdx-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
iomap: fix Invalid License ID
treewide: remove SPDX "WITH Linux-syscall-note" from kernel-space headers again
treewide: add "WITH Linux-syscall-note" to SPDX tag of uapi headers
from the massive RST conversion; a few other small fixes as well.
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Merge tag 'docs-5.3-1' of git://git.lwn.net/linux
Pull documentation fixes from Jonathan Corbet:
"This is mostly a set of follow-on fixes from Mauro fixing various
fallout from the massive RST conversion; a few other small fixes as
well"
* tag 'docs-5.3-1' of git://git.lwn.net/linux: (21 commits)
docs: phy: Drop duplicate 'be made'
doc:it_IT: translations in process/
docs/vm: transhuge: fix typo in madvise reference
doc:it_IT: rephrase statement
doc:it_IT: align translation to mainline
docs: load_config.py: ensure subdirs end with "/"
docs: virtual: add it to the documentation body
docs: remove extra conf.py files
docs: load_config.py: avoid needing a conf.py just due to LaTeX docs
scripts/sphinx-pre-install: seek for Noto CJK fonts for pdf output
scripts/sphinx-pre-install: cleanup Gentoo checks
scripts/sphinx-pre-install: fix latexmk dependencies
scripts/sphinx-pre-install: don't use LaTeX with CentOS 7
scripts/sphinx-pre-install: fix script for RHEL/CentOS
docs: conf.py: only use CJK if the font is available
docs: conf.py: add CJK package needed by translations
docs: pdf: add all Documentation/*/index.rst to PDF output
docs: fix broken doc references due to renames
docs: power: add it to to the main documentation index
docs: powerpc: convert docs to ReST and rename to *.rst
...
UAPI headers licensed under GPL are supposed to have exception
"WITH Linux-syscall-note" so that they can be included into non-GPL
user space application code.
The exception note is missing in some UAPI headers.
Some of them slipped in by the treewide conversion commit b24413180f
("License cleanup: add SPDX GPL-2.0 license identifier to files with
no license"). Just run:
$ git show --oneline b24413180f -- arch/x86/include/uapi/asm/
I believe they are not intentional, and should be fixed too.
This patch was generated by the following script:
git grep -l --not -e Linux-syscall-note --and -e SPDX-License-Identifier \
-- :arch/*/include/uapi/asm/*.h :include/uapi/ :^*/Kbuild |
while read file
do
sed -i -e '/[[:space:]]OR[[:space:]]/s/\(GPL-[^[:space:]]*\)/(\1 WITH Linux-syscall-note)/g' \
-e '/[[:space:]]or[[:space:]]/s/\(GPL-[^[:space:]]*\)/(\1 WITH Linux-syscall-note)/g' \
-e '/[[:space:]]OR[[:space:]]/!{/[[:space:]]or[[:space:]]/!s/\(GPL-[^[:space:]]*\)/\1 WITH Linux-syscall-note/g}' $file
done
After this patch is applied, there are 5 UAPI headers that do not contain
"WITH Linux-syscall-note". They are kept untouched since this exception
applies only to GPL variants.
$ git grep --not -e Linux-syscall-note --and -e SPDX-License-Identifier \
-- :arch/*/include/uapi/asm/*.h :include/uapi/ :^*/Kbuild
include/uapi/drm/panfrost_drm.h:/* SPDX-License-Identifier: MIT */
include/uapi/linux/batman_adv.h:/* SPDX-License-Identifier: MIT */
include/uapi/linux/qemu_fw_cfg.h:/* SPDX-License-Identifier: BSD-3-Clause */
include/uapi/linux/vbox_err.h:/* SPDX-License-Identifier: MIT */
include/uapi/linux/virtio_iommu.h:/* SPDX-License-Identifier: BSD-3-Clause */
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
An assortment of non-regression fixes that have accumulated since the start of
the merge window.
A fix for a user triggerable oops on machines where transactional memory is
disabled, eg. Power9 bare metal, Power8 with TM disabled on the command line, or
all Power7 or earlier machines.
Three fixes for handling of PMU and power saving registers when running nested
KVM on Power9.
Two fixes for bugs found while stress testing the XIVE interrupt controller
code, also on Power9.
A fix to allow guests to boot under Qemu/KVM on Power9 using the the Hash MMU
with >= 1TB of memory.
Two fixes for bugs in the recent DMA cleanup, one of which could lead to
checkstops.
And finally three fixes for the PAPR SCM nvdimm driver.
Thanks to:
Alexey Kardashevskiy, Andrea Arcangeli, Cédric Le Goater, Christoph Hellwig,
David Gibson, Gautham R. Shenoy, Michael Neuling, Oliver O'Halloran,, Satheesh
Rajendran, Shawn Anastasio, Suraj Jitindar Singh, Vaibhav Jain.
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Merge tag 'powerpc-5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"An assortment of non-regression fixes that have accumulated since the
start of the merge window.
- A fix for a user triggerable oops on machines where transactional
memory is disabled, eg. Power9 bare metal, Power8 with TM disabled
on the command line, or all Power7 or earlier machines.
- Three fixes for handling of PMU and power saving registers when
running nested KVM on Power9.
- Two fixes for bugs found while stress testing the XIVE interrupt
controller code, also on Power9.
- A fix to allow guests to boot under Qemu/KVM on Power9 using the
the Hash MMU with >= 1TB of memory.
- Two fixes for bugs in the recent DMA cleanup, one of which could
lead to checkstops.
- And finally three fixes for the PAPR SCM nvdimm driver.
Thanks to: Alexey Kardashevskiy, Andrea Arcangeli, Cédric Le Goater,
Christoph Hellwig, David Gibson, Gautham R. Shenoy, Michael Neuling,
Oliver O'Halloran, Satheesh Rajendran, Shawn Anastasio, Suraj Jitindar
Singh, Vaibhav Jain"
* tag 'powerpc-5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/papr_scm: Force a scm-unbind if initial scm-bind fails
powerpc/papr_scm: Update drc_pmem_unbind() to use H_SCM_UNBIND_ALL
powerpc/pseries: Update SCM hcall op-codes in hvcall.h
powerpc/tm: Fix oops on sigreturn on systems without TM
powerpc/dma: Fix invalid DMA mmap behavior
KVM: PPC: Book3S HV: XIVE: fix rollback when kvmppc_xive_create fails
powerpc/xive: Fix loop exit-condition in xive_find_target_in_mask()
powerpc: fix off by one in max_zone_pfn initialization for ZONE_DMA
KVM: PPC: Book3S HV: Save and restore guest visible PSSCR bits on pseries
powerpc/pmu: Set pmcregs_in_use in paca when running as LPAR
KVM: PPC: Book3S HV: Always save guest pmu for guest capable of nesting
powerpc/mm: Limit rma_size to 1TB when running without HV mode
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"Bugfixes, a pvspinlock optimization, and documentation moving"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: X86: Boost queue head vCPU to mitigate lock waiter preemption
Documentation: move Documentation/virtual to Documentation/virt
KVM: nVMX: Set cached_vmcs12 and cached_shadow_vmcs12 NULL after free
KVM: X86: Dynamically allocate user_fpu
KVM: X86: Fix fpu state crash in kvm guest
Revert "kvm: x86: Use task structs fpu field for user"
KVM: nVMX: Clear pending KVM_REQ_GET_VMCS12_PAGES when leaving nested
Renaming docs seems to be en vogue at the moment, so fix on of the
grossly misnamed directories. We usually never use "virtual" as
a shortcut for virtualization in the kernel, but always virt,
as seen in the virt/ top-level directory. Fix up the documentation
to match that.
Fixes: ed16648eb5 ("Move kvm, uml, and lguest subdirectories under a common "virtual" directory, I.E:")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In some cases initial bind of scm memory for an lpar can fail if
previously it wasn't released using a scm-unbind hcall. This situation
can arise due to panic of the previous kernel or forced lpar
fadump. In such cases the H_SCM_BIND_MEM return a H_OVERLAP error.
To mitigate such cases the patch updates papr_scm_probe() to force a
call to drc_pmem_unbind() in case the initial bind of scm memory fails
with EBUSY error. In case scm-bind operation again fails after the
forced scm-unbind then we follow the existing error path. We also
update drc_pmem_bind() to handle the H_OVERLAP error returned by phyp
and indicate it as a EBUSY error back to the caller.
Suggested-by: "Oliver O'Halloran" <oohall@gmail.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190629160610.23402-4-vaibhav@linux.ibm.com
The new hcall named H_SCM_UNBIND_ALL has been introduce that can
unbind all or specific scm memory assigned to an lpar. This is
more efficient than using H_SCM_UNBIND_MEM as currently we don't
support partial unbind of scm memory.
Hence this patch proposes following changes to drc_pmem_unbind():
* Update drc_pmem_unbind() to replace hcall H_SCM_UNBIND_MEM to
H_SCM_UNBIND_ALL.
* Update drc_pmem_unbind() to handles cases when PHYP asks the guest
kernel to wait for specific amount of time before retrying the
hcall via the 'LONG_BUSY' return value.
* Ensure appropriate error code is returned back from the function
in case of an error.
Reviewed-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190629160610.23402-3-vaibhav@linux.ibm.com
Update the hvcalls.h to include op-codes for new hcalls introduce to
manage SCM memory. Also update existing hcall definitions to reflect
current papr specification for SCM.
The removed hcall op-codes H_SCM_MEM_QUERY, H_SCM_BLOCK_CLEAR were
transient proposals and there support was never implemented by
Power-VM nor they were used anywhere in Linux kernel. Hence we don't
expect anyone to be impacted by this change.
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190629160610.23402-2-vaibhav@linux.ibm.com
On systems like P9 powernv where we have no TM (or P8 booted with
ppc_tm=off), userspace can construct a signal context which still has
the MSR TS bits set. The kernel tries to restore this context which
results in the following crash:
Unexpected TM Bad Thing exception at c0000000000022fc (msr 0x8000000102a03031) tm_scratch=800000020280f033
Oops: Unrecoverable exception, sig: 6 [#1]
LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
Modules linked in:
CPU: 0 PID: 1636 Comm: sigfuz Not tainted 5.2.0-11043-g0a8ad0ffa4 #69
NIP: c0000000000022fc LR: 00007fffb2d67e48 CTR: 0000000000000000
REGS: c00000003fffbd70 TRAP: 0700 Not tainted (5.2.0-11045-g7142b497d8)
MSR: 8000000102a03031 <SF,VEC,VSX,FP,ME,IR,DR,LE,TM[E]> CR: 42004242 XER: 00000000
CFAR: c0000000000022e0 IRQMASK: 0
GPR00: 0000000000000072 00007fffb2b6e560 00007fffb2d87f00 0000000000000669
GPR04: 00007fffb2b6e728 0000000000000000 0000000000000000 00007fffb2b6f2a8
GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR12: 0000000000000000 00007fffb2b76900 0000000000000000 0000000000000000
GPR16: 00007fffb2370000 00007fffb2d84390 00007fffea3a15ac 000001000a250420
GPR20: 00007fffb2b6f260 0000000010001770 0000000000000000 0000000000000000
GPR24: 00007fffb2d843a0 00007fffea3a14a0 0000000000010000 0000000000800000
GPR28: 00007fffea3a14d8 00000000003d0f00 0000000000000000 00007fffb2b6e728
NIP [c0000000000022fc] rfi_flush_fallback+0x7c/0x80
LR [00007fffb2d67e48] 0x7fffb2d67e48
Call Trace:
Instruction dump:
e96a0220 e96a02a8 e96a0330 e96a03b8 394a0400 4200ffdc 7d2903a6 e92d0c00
e94d0c08 e96d0c10 e82d0c18 7db242a6 <4c000024> 7db243a6 7db142a6 f82d0c18
The problem is the signal code assumes TM is enabled when
CONFIG_PPC_TRANSACTIONAL_MEM is enabled. This may not be the case as
with P9 powernv or if `ppc_tm=off` is used on P8.
This means any local user can crash the system.
Fix the problem by returning a bad stack frame to the user if they try
to set the MSR TS bits with sigreturn() on systems where TM is not
supported.
Found with sigfuz kernel selftest on P9.
This fixes CVE-2019-13648.
Fixes: 2b0a576d15 ("powerpc: Add new transactional memory state to the signal context")
Cc: stable@vger.kernel.org # v3.9
Reported-by: Praveen Pandey <Praveen.Pandey@in.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190719050502.405-1-mikey@neuling.org
The refactor of powerpc DMA functions in commit 6666cc17d7
("powerpc/dma: remove dma_nommu_mmap_coherent") incorrectly
changes the way DMA mappings are handled on powerpc.
Since this change, all mapped pages are marked as cache-inhibited
through the default implementation of arch_dma_mmap_pgprot.
This differs from the previous behavior of only marking pages
in noncoherent mappings as cache-inhibited and has resulted in
sporadic system crashes in certain hardware configurations and
workloads (see Bugzilla).
This commit restores the previous correct behavior by providing
an implementation of arch_dma_mmap_pgprot that only marks
pages in noncoherent mappings as cache-inhibited. As this behavior
should be universal for all powerpc platforms a new file,
dma-generic.c, was created to store it.
Fixes: 6666cc17d7 ("powerpc/dma: remove dma_nommu_mmap_coherent")
# NOTE: fixes commit 6666cc17d7 released in v5.1.
# Consider a stable tag:
# Cc: stable@vger.kernel.org # v5.1+
# NOTE: fixes commit 6666cc17d7 released in v5.1.
# Consider a stable tag:
# Cc: stable@vger.kernel.org # v5.1+
Cc: stable@vger.kernel.org # v5.1+
Signed-off-by: Shawn Anastasio <shawn@anastas.io>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190717235437.12908-1-shawn@anastas.io
The XIVE device structure is now allocated in kvmppc_xive_get_device()
and kfree'd in kvmppc_core_destroy_vm(). In case of an OPAL error when
allocating the XIVE VPs, the kfree() call in kvmppc_xive_*create()
will result in a double free and corrupt the host memory.
Fixes: 5422e95103 ("KVM: PPC: Book3S HV: XIVE: Replace the 'destroy' method by a 'release' method")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/6ea6998b-a890-2511-01d1-747d7621eb19@kaod.org
walk_memory_range() was once used to iterate over sections. Now, it
iterates over memory blocks. Rename the function, fixup the
documentation.
Also, pass start+size instead of PFNs, which is what most callers
already have at hand. (we'll rework link_mem_sections() most probably
soon)
Follow-up patches will rework, simplify, and move walk_memory_blocks()
to drivers/base/memory.c.
Note: walk_memory_blocks() only works correctly right now if the
start_pfn is aligned to a section start. This is the case right now,
but we'll generalize the function in a follow up patch so the semantics
match the documentation.
[akpm@linux-foundation.org: remove unused variable]
Link: http://lkml.kernel.org/r/20190614100114.311-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Rashmica Gupta <rashmica.g@gmail.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Arun KS <arunks@codeaurora.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We want to improve error handling while adding memory by allowing to use
arch_remove_memory() and __remove_pages() even if
CONFIG_MEMORY_HOTREMOVE is not set to e.g., implement something like:
arch_add_memory()
rc = do_something();
if (rc) {
arch_remove_memory();
}
We won't get rid of CONFIG_MEMORY_HOTREMOVE for now, as it will require
quite some dependencies for memory offlining.
Link: http://lkml.kernel.org/r/20190527111152.16324-7-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Mark Brown <broonie@kernel.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: "mike.travis@hpe.com" <mike.travis@hpe.com>
Cc: Andrew Banman <andrew.banman@hpe.com>
Cc: Arun KS <arunks@codeaurora.org>
Cc: Qian Cai <cai@lca.pw>
Cc: Mathieu Malaterre <malat@debian.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chintan Pandya <cpandya@codeaurora.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Jun Yao <yaojun8558363@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
xive_find_target_in_mask() has the following for(;;) loop which has a
bug when @first == cpumask_first(@mask) and condition 1 fails to hold
for every CPU in @mask. In this case we loop forever in the for-loop.
first = cpu;
for (;;) {
if (cpu_online(cpu) && xive_try_pick_target(cpu)) // condition 1
return cpu;
cpu = cpumask_next(cpu, mask);
if (cpu == first) // condition 2
break;
if (cpu >= nr_cpu_ids) // condition 3
cpu = cpumask_first(mask);
}
This is because, when @first == cpumask_first(@mask), we never hit the
condition 2 (cpu == first) since prior to this check, we would have
executed "cpu = cpumask_next(cpu, mask)" which will set the value of
@cpu to a value greater than @first or to nr_cpus_ids. When this is
coupled with the fact that condition 1 is not met, we will never exit
this loop.
This was discovered by the hard-lockup detector while running LTP test
concurrently with SMT switch tests.
watchdog: CPU 12 detected hard LOCKUP on other CPUs 68
watchdog: CPU 12 TB:85587019220796, last SMP heartbeat TB:85578827223399 (15999ms ago)
watchdog: CPU 68 Hard LOCKUP
watchdog: CPU 68 TB:85587019361273, last heartbeat TB:85576815065016 (19930ms ago)
CPU: 68 PID: 45050 Comm: hxediag Kdump: loaded Not tainted 4.18.0-100.el8.ppc64le #1
NIP: c0000000006f5578 LR: c000000000cba9ec CTR: 0000000000000000
REGS: c000201fff3c7d80 TRAP: 0100 Not tainted (4.18.0-100.el8.ppc64le)
MSR: 9000000002883033 <SF,HV,VEC,VSX,FP,ME,IR,DR,RI,LE> CR: 24028424 XER: 00000000
CFAR: c0000000006f558c IRQMASK: 1
GPR00: c0000000000afc58 c000201c01c43400 c0000000015ce500 c000201cae26ec18
GPR04: 0000000000000800 0000000000000540 0000000000000800 00000000000000f8
GPR08: 0000000000000020 00000000000000a8 0000000080000000 c00800001a1beed8
GPR12: c0000000000b1410 c000201fff7f4c00 0000000000000000 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000540 0000000000000001
GPR20: 0000000000000048 0000000010110000 c00800001a1e3780 c000201cae26ed18
GPR24: 0000000000000000 c000201cae26ed8c 0000000000000001 c000000001116bc0
GPR28: c000000001601ee8 c000000001602494 c000201cae26ec18 000000000000001f
NIP [c0000000006f5578] find_next_bit+0x38/0x90
LR [c000000000cba9ec] cpumask_next+0x2c/0x50
Call Trace:
[c000201c01c43400] [c000201cae26ec18] 0xc000201cae26ec18 (unreliable)
[c000201c01c43420] [c0000000000afc58] xive_find_target_in_mask+0x1b8/0x240
[c000201c01c43470] [c0000000000b0228] xive_pick_irq_target.isra.3+0x168/0x1f0
[c000201c01c435c0] [c0000000000b1470] xive_irq_startup+0x60/0x260
[c000201c01c43640] [c0000000001d8328] __irq_startup+0x58/0xf0
[c000201c01c43670] [c0000000001d844c] irq_startup+0x8c/0x1a0
[c000201c01c436b0] [c0000000001d57b0] __setup_irq+0x9f0/0xa90
[c000201c01c43760] [c0000000001d5aa0] request_threaded_irq+0x140/0x220
[c000201c01c437d0] [c00800001a17b3d4] bnx2x_nic_load+0x188c/0x3040 [bnx2x]
[c000201c01c43950] [c00800001a187c44] bnx2x_self_test+0x1fc/0x1f70 [bnx2x]
[c000201c01c43a90] [c000000000adc748] dev_ethtool+0x11d8/0x2cb0
[c000201c01c43b60] [c000000000b0b61c] dev_ioctl+0x5ac/0xa50
[c000201c01c43bf0] [c000000000a8d4ec] sock_do_ioctl+0xbc/0x1b0
[c000201c01c43c60] [c000000000a8dfb8] sock_ioctl+0x258/0x4f0
[c000201c01c43d20] [c0000000004c9704] do_vfs_ioctl+0xd4/0xa70
[c000201c01c43de0] [c0000000004ca274] sys_ioctl+0xc4/0x160
[c000201c01c43e30] [c00000000000b388] system_call+0x5c/0x70
Instruction dump:
78aad182 54a806be 3920ffff 78a50664 794a1f24 7d294036 7d43502a 7d295039
4182001c 48000034 78a9d182 79291f24 <7d23482a> 2fa90000 409e0020 38a50040
To fix this, move the check for condition 2 after the check for
condition 3, so that we are able to break out of the loop soon after
iterating through all the CPUs in the @mask in the problem case. Use
do..while() to achieve this.
Fixes: 243e25112d ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.12+
Reported-by: Indira P. Joga <indira.priya@in.ibm.com>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1563359724-13931-1-git-send-email-ego@linux.vnet.ibm.com
Merge more updates from Andrew Morton:
"VM:
- z3fold fixes and enhancements by Henry Burns and Vitaly Wool
- more accurate reclaimed slab caches calculations by Yafang Shao
- fix MAP_UNINITIALIZED UAPI symbol to not depend on config, by
Christoph Hellwig
- !CONFIG_MMU fixes by Christoph Hellwig
- new novmcoredd parameter to omit device dumps from vmcore, by
Kairui Song
- new test_meminit module for testing heap and pagealloc
initialization, by Alexander Potapenko
- ioremap improvements for huge mappings, by Anshuman Khandual
- generalize kprobe page fault handling, by Anshuman Khandual
- device-dax hotplug fixes and improvements, by Pavel Tatashin
- enable synchronous DAX fault on powerpc, by Aneesh Kumar K.V
- add pte_devmap() support for arm64, by Robin Murphy
- unify locked_vm accounting with a helper, by Daniel Jordan
- several misc fixes
core/lib:
- new typeof_member() macro including some users, by Alexey Dobriyan
- make BIT() and GENMASK() available in asm, by Masahiro Yamada
- changed LIST_POISON2 on x86_64 to 0xdead000000000122 for better
code generation, by Alexey Dobriyan
- rbtree code size optimizations, by Michel Lespinasse
- convert struct pid count to refcount_t, by Joel Fernandes
get_maintainer.pl:
- add --no-moderated switch to skip moderated ML's, by Joe Perches
misc:
- ptrace PTRACE_GET_SYSCALL_INFO interface
- coda updates
- gdb scripts, various"
[ Using merge message suggestion from Vlastimil Babka, with some editing - Linus ]
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (100 commits)
fs/select.c: use struct_size() in kmalloc()
mm: add account_locked_vm utility function
arm64: mm: implement pte_devmap support
mm: introduce ARCH_HAS_PTE_DEVMAP
mm: clean up is_device_*_page() definitions
mm/mmap: move common defines to mman-common.h
mm: move MAP_SYNC to asm-generic/mman-common.h
device-dax: "Hotremove" persistent memory that is used like normal RAM
mm/hotplug: make remove_memory() interface usable
device-dax: fix memory and resource leak if hotplug fails
include/linux/lz4.h: fix spelling and copy-paste errors in documentation
ipc/mqueue.c: only perform resource calculation if user valid
include/asm-generic/bug.h: fix "cut here" for WARN_ON for __WARN_TAINT architectures
scripts/gdb: add helpers to find and list devices
scripts/gdb: add lx-genpd-summary command
drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl
kernel/pid.c: convert struct pid count to refcount_t
drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings
select: shift restore_saved_sigmask_unless() into poll_select_copy_remaining()
select: change do_poll() to return -ERESTARTNOHAND rather than -EINTR
...
Convert docs to ReST and add them to the arch-specific
book.
The conversion here was trivial, as almost every file there
was already using an elegant format close to ReST standard.
The changes were mostly to mark literal blocks and add a few
missing section title identifiers.
One note with regards to "--": on Sphinx, this can't be used
to identify a list, as it will format it badly. This can be
used, however, to identify a long hyphen - and "---" is an
even longer one.
At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> # cxl
locked_vm accounting is done roughly the same way in five places, so
unify them in a helper.
Include the helper's caller in the debug print to distinguish between
callsites.
Error codes stay the same, so user-visible behavior does too. The one
exception is that the -EPERM case in tce_account_locked_vm is removed
because Alexey has never seen it triggered.
[daniel.m.jordan@oracle.com: v3]
Link: http://lkml.kernel.org/r/20190529205019.20927-1-daniel.m.jordan@oracle.com
[sfr@canb.auug.org.au: fix mm/util.c]
Link: http://lkml.kernel.org/r/20190524175045.26897-1-daniel.m.jordan@oracle.com
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Cc: Alan Tull <atull@kernel.org>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Moritz Fischer <mdf@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Steve Sistare <steven.sistare@oracle.com>
Cc: Wu Hao <hao.wu@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ARCH_HAS_ZONE_DEVICE is somewhat meaningless in itself, and combined
with the long-out-of-date comment can lead to the impression than an
architecture may just enable it (since __add_pages() now "comprehends
device memory" for itself) and expect things to work.
In practice, however, ZONE_DEVICE users have little chance of
functioning correctly without __HAVE_ARCH_PTE_DEVMAP, so let's clean
that up the same way as ARCH_HAS_PTE_SPECIAL and make it the proper
dependency so the real situation is clearer.
Link: http://lkml.kernel.org/r/87554aa78478a02a63f2c4cf60a847279ae3eb3b.1558547956.git.robin.murphy@arm.com
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
