linux-stable.git/arch/powerpc/sysdev/xive, branch v5.10.78

powerpc/xive: Discard disabled interrupts in get_irqchip_state()

2021-10-20T09:45:01+00:00

commit 6f779e1d359b8d5801f677c1d49dcfa10bf95674 upstream.

When an interrupt is passed through, the KVM XIVE device calls the
set_vcpu_affinity() handler which raises the P bit to mask the
interrupt and to catch any in-flight interrupts while routing the
interrupt to the guest.

On the guest side, drivers (like some Intels) can request at probe
time some MSIs and call synchronize_irq() to check that there are no
in flight interrupts. This will call the XIVE get_irqchip_state()
handler which will always return true as the interrupt P bit has been
set on the host side and lock the CPU in an infinite loop.

Fix that by discarding disabled interrupts in get_irqchip_state().

Fixes: da15c03b047d ("powerpc/xive: Implement get_irqchip_state method for XIVE to fix shutdown race")
Cc: stable@vger.kernel.org #v5.4+
Signed-off-by: Cédric Le Goater 
Tested-by: seeteena 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20211011070203.99726-1-clg@kaod.org
Signed-off-by: Greg Kroah-Hartman

powerpc/xive: Fix xmon command "dxi"

2021-05-14T07:50:38+00:00

[ Upstream commit 33e4bc5946432a4ac173fd08e8e30a13ab94d06d ]

When under xmon, the "dxi" command dumps the state of the XIVE
interrupts. If an interrupt number is specified, only the state of
the associated XIVE interrupt is dumped. This form of the command
lacks an irq_data parameter which is nevertheless used by
xmon_xive_get_irq_config(), leading to an xmon crash.

Fix that by doing a lookup in the system IRQ mapping to query the IRQ
descriptor data. Invalid interrupt numbers, or not belonging to the
XIVE IRQ domain, OPAL event interrupt number for instance, should be
caught by the previous query done at the firmware level.

Fixes: 97ef27507793 ("powerpc/xive: Fix xmon support on the PowerNV platform")
Reported-by: kernel test robot 
Reported-by: Dan Carpenter 
Signed-off-by: Cédric Le Goater 
Tested-by: Greg Kurz 
Reviewed-by: Greg Kurz 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210331144514.892250-8-clg@kaod.org
Signed-off-by: Sasha Levin

powerpc/xive: Drop check on irq_data in xive_core_debug_show()

2021-05-14T07:50:38+00:00

[ Upstream commit a74ce5926b20cd0e6d624a9b2527073a96dfed7f ]

When looping on IRQ descriptor, irq_data is always valid.

Fixes: 930914b7d528 ("powerpc/xive: Add a debugfs file to dump internal XIVE state")
Reported-by: kernel test robot 
Reported-by: Dan Carpenter 
Signed-off-by: Cédric Le Goater 
Reviewed-by: Greg Kurz 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20210331144514.892250-6-clg@kaod.org
Signed-off-by: Sasha Levin

powerpc/xive: Make debug routines static

2020-09-18T10:05:25+00:00

This fixes a compile error with W=1.

CC      arch/powerpc/sysdev/xive/common.o
../arch/powerpc/sysdev/xive/common.c:1568:6: error: no previous prototype for ‘xive_debug_show_cpu’ [-Werror=missing-prototypes]
 void xive_debug_show_cpu(struct seq_file *m, int cpu)
      ^~~~~~~~~~~~~~~~~~~
../arch/powerpc/sysdev/xive/common.c:1602:6: error: no previous prototype for ‘xive_debug_show_irq’ [-Werror=missing-prototypes]
 void xive_debug_show_irq(struct seq_file *m, u32 hw_irq, struct irq_data *d)
      ^~~~~~~~~~~~~~~~~~~

Fixes: 930914b7d528 ("powerpc/xive: Add a debugfs file to dump internal XIVE state")
Signed-off-by: Cédric Le Goater 
Reviewed-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200914211007.2285999-5-clg@kaod.org

powerpc: fix function annotations to avoid section mismatch warnings with gcc-10

2020-07-30T00:50:07+00:00

Certain warnings are emitted for powerpc code when building with a gcc-10
toolset:

    WARNING: modpost: vmlinux.o(.text.unlikely+0x377c): Section mismatch in
    reference from the function remove_pmd_table() to the function
    .meminit.text:split_kernel_mapping()
    The function remove_pmd_table() references
    the function __meminit split_kernel_mapping().
    This is often because remove_pmd_table lacks a __meminit
    annotation or the annotation of split_kernel_mapping is wrong.

Add the appropriate __init and __meminit annotations to make modpost not
complain. In all the cases there are just a single callsite from another
__init or __meminit function:

__meminit remove_pagetable() -> remove_pud_table() -> remove_pmd_table()
__init prom_init() -> setup_secure_guest()
__init xive_spapr_init() -> xive_spapr_disabled()

Signed-off-by: Vladis Dronov 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200729133741.62789-1-vdronov@redhat.com

powerpc/xive: Ignore kmemleak false positives

2020-06-22T00:37:57+00:00

xive_native_provision_pages() allocates memory and passes the pointer to
OPAL so kmemleak cannot find the pointer usage in the kernel memory and
produces a false positive report (below) (even if the kernel did scan
OPAL memory, it is unable to deal with __pa() addresses anyway).

This silences the warning.

unreferenced object 0xc000200350c40000 (size 65536):
  comm "qemu-system-ppc", pid 2725, jiffies 4294946414 (age 70776.530s)
  hex dump (first 32 bytes):
    02 00 00 00 50 00 00 00 00 00 00 00 00 00 00 00  ....P...........
    01 00 08 07 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<0000000081ff046c>] xive_native_alloc_vp_block+0x120/0x250
    [<00000000d555d524>] kvmppc_xive_compute_vp_id+0x248/0x350 [kvm]
    [<00000000d69b9c9f>] kvmppc_xive_connect_vcpu+0xc0/0x520 [kvm]
    [<000000006acbc81c>] kvm_arch_vcpu_ioctl+0x308/0x580 [kvm]
    [<0000000089c69580>] kvm_vcpu_ioctl+0x19c/0xae0 [kvm]
    [<00000000902ae91e>] ksys_ioctl+0x184/0x1b0
    [<00000000f3e68bd7>] sys_ioctl+0x48/0xb0
    [<0000000001b2c127>] system_call_exception+0x124/0x1f0
    [<00000000d2b2ee40>] system_call_common+0xe8/0x214

Signed-off-by: Alexey Kardashevskiy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200612043303.84894-1-aik@ozlabs.ru

powerpc/xive: Share the event-queue page with the Hypervisor.

2020-05-28T13:24:40+00:00

XIVE interrupt controller uses an Event Queue (EQ) to enqueue event
notifications when an exception occurs. The EQ is a single memory page
provided by the O/S defining a circular buffer, one per server and
priority couple.

On baremetal, the EQ page is configured with an OPAL call. On pseries,
an extra hop is necessary and the guest OS uses the hcall
H_INT_SET_QUEUE_CONFIG to configure the XIVE interrupt controller.

The XIVE controller being Hypervisor privileged, it will not be allowed
to enqueue event notifications for a Secure VM unless the EQ pages are
shared by the Secure VM.

Hypervisor/Ultravisor still requires support for the TIMA and ESB page
fault handlers. Until this is complete, QEMU can use the emulated XIVE
device for Secure VMs, option "kernel_irqchip=off" on the QEMU pseries
machine.

Signed-off-by: Ram Pai 
Reviewed-by: Cedric Le Goater 
Reviewed-by: Greg Kurz 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200426020518.GC5853@oc0525413822.ibm.com

powerpc/xive: Do not expose a debugfs file when XIVE is disabled

2020-05-28T13:24:32+00:00

The XIVE interrupt mode can be disabled with the "xive=off" kernel
parameter, in which case there is nothing to present to the user in the
associated /sys/kernel/debug/powerpc/xive file.

Fixes: 930914b7d528 ("powerpc/xive: Add a debugfs file to dump internal XIVE state")
Signed-off-by: Cédric Le Goater 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200429075122.1216388-4-clg@kaod.org

powerpc/xive: Clear the page tables for the ESB IO mapping

2020-05-26T13:37:14+00:00

Commit 1ca3dec2b2df ("powerpc/xive: Prevent page fault issues in the
machine crash handler") fixed an issue in the FW assisted dump of
machines using hash MMU and the XIVE interrupt mode under the POWER
hypervisor. It forced the mapping of the ESB page of interrupts being
mapped in the Linux IRQ number space to make sure the 'crash kexec'
sequence worked during such an event. But it didn't handle the
un-mapping.

This mapping is now blocking the removal of a passthrough IO adapter
under the POWER hypervisor because it expects the guest OS to have
cleared all page table entries related to the adapter. If some are
still present, the RTAS call which isolates the PCI slot returns error
9001 "valid outstanding translations".

Remove these mapping in the IRQ data cleanup routine.

Under KVM, this cleanup is not required because the ESB pages for the
adapter interrupts are un-mapped from the guest by the hypervisor in
the KVM XIVE native device. This is now redundant but it's harmless.

Fixes: 1ca3dec2b2df ("powerpc/xive: Prevent page fault issues in the machine crash handler")
Cc: stable@vger.kernel.org # v5.5+
Signed-off-by: Cédric Le Goater 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200429075122.1216388-2-clg@kaod.org

Merge branch 'topic/ppc-kvm' into next

2020-05-20T13:38:13+00:00

Merge our topic branch shared with the kvm-ppc tree.

This brings in one commit that touches the XIVE interrupt controller
logic across core and KVM code.