linux-toradex.git/arch/powerpc/sysdev/xive/spapr.c, branch v5.7-rc5

powerpc/xive: Add a debugfs file to dump internal XIVE state

2020-03-26T13:20:38+00:00

As does XMON, the debugfs file /sys/kernel/debug/powerpc/xive exposes
the XIVE internal state of the machine CPUs and interrupts. Available
on the PowerNV and sPAPR platforms.

Signed-off-by: Cédric Le Goater 
[mpe: Make the debugfs file 0400]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200306150143.5551-5-clg@kaod.org

powerpc/xive: Use XIVE_BAD_IRQ instead of zero to catch non configured IPIs

2020-03-26T13:19:04+00:00

When a CPU is brought up, an IPI number is allocated and recorded
under the XIVE CPU structure. Invalid IPI numbers are tracked with
interrupt number 0x0.

On the PowerNV platform, the interrupt number space starts at 0x10 and
this works fine. However, on the sPAPR platform, it is possible to
allocate the interrupt number 0x0 and this raises an issue when CPU 0
is unplugged. The XIVE spapr driver tracks allocated interrupt numbers
in a bitmask and it is not correctly updated when interrupt number 0x0
is freed. It stays allocated and it is then impossible to reallocate.

Fix by using the XIVE_BAD_IRQ value instead of zero on both platforms.

Reported-by: David Gibson 
Fixes: eac1e731b59e ("powerpc/xive: guest exploitation of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Cédric Le Goater 
Reviewed-by: David Gibson 
Tested-by: David Gibson 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200306150143.5551-2-clg@kaod.org

powerpc/xive: Skip ioremap() of ESB pages for LSI interrupts

2019-12-04T13:11:45+00:00

The PCI INTx interrupts and other LSI interrupts are handled differently
under a sPAPR platform. When the interrupt source characteristics are
queried, the hypervisor returns an H_INT_ESB flag to inform the OS
that it should be using the H_INT_ESB hcall for interrupt management
and not loads and stores on the interrupt ESB pages.

A default -1 value is returned for the addresses of the ESB pages. The
driver ignores this condition today and performs a bogus IO mapping.
Recent changes and the DEBUG_VM configuration option make the bug
visible with :

  kernel BUG at arch/powerpc/include/asm/book3s/64/pgtable.h:612!
  Oops: Exception in kernel mode, sig: 5 [#1]
  LE PAGE_SIZE=64K MMU=Radix MMU=Hash SMP NR_CPUS=1024 NUMA pSeries
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.4.0-0.rc6.git0.1.fc32.ppc64le #1
  NIP:  c000000000f63294 LR: c000000000f62e44 CTR: 0000000000000000
  REGS: c0000000fa45f0d0 TRAP: 0700   Not tainted  (5.4.0-0.rc6.git0.1.fc32.ppc64le)
  ...
  NIP ioremap_page_range+0x4c4/0x6e0
  LR  ioremap_page_range+0x74/0x6e0
  Call Trace:
    ioremap_page_range+0x74/0x6e0 (unreliable)
    do_ioremap+0x8c/0x120
    __ioremap_caller+0x128/0x140
    ioremap+0x30/0x50
    xive_spapr_populate_irq_data+0x170/0x260
    xive_irq_domain_map+0x8c/0x170
    irq_domain_associate+0xb4/0x2d0
    irq_create_mapping+0x1e0/0x3b0
    irq_create_fwspec_mapping+0x27c/0x3e0
    irq_create_of_mapping+0x98/0xb0
    of_irq_parse_and_map_pci+0x168/0x230
    pcibios_setup_device+0x88/0x250
    pcibios_setup_bus_devices+0x54/0x100
    __of_scan_bus+0x160/0x310
    pcibios_scan_phb+0x330/0x390
    pcibios_init+0x8c/0x128
    do_one_initcall+0x60/0x2c0
    kernel_init_freeable+0x290/0x378
    kernel_init+0x2c/0x148
    ret_from_kernel_thread+0x5c/0x80

Fixes: bed81ee181dd ("powerpc/xive: introduce H_INT_ESB hcall")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Cédric Le Goater 
Tested-by: Daniel Axtens 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20191203163642.2428-1-clg@kaod.org

powerpc/xive: Fix dump of XIVE interrupt under pseries

2019-08-19T03:20:24+00:00

The xmon 'dxi' command calls OPAL to query the XIVE configuration of a
interrupt. This can only be done on baremetal (PowerNV) and it will
crash a pseries machine.

Introduce a new XIVE get_irq_config() operation which implements a
different query depending on the platform, PowerNV or pseries, and
modify xmon to use a top level wrapper.

Signed-off-by: Cédric Le Goater 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20190814154754.23682-3-clg@kaod.org

powerpc/xive: Add a check for memory allocation failure

2019-08-15T12:52:55+00:00

The result of this kzalloc is not checked. Add a check and corresponding
error handling code.

Signed-off-by: Christophe JAILLET 
Reviewed-by: Greg Kurz 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/cc53462734dfeaf15b6bad0e626b483de18656b4.1564647619.git.christophe.jaillet@wanadoo.fr

powerpc/xive: Use GFP_KERNEL instead of GFP_ATOMIC in 'xive_irq_bitmap_add()'

2019-08-15T12:52:55+00:00

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 
Reviewed-by: Cédric Le Goater 
Reviewed-by: Greg Kurz 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/85d5d247ce753befd6aa63c473f7823de6520ccd.1564647619.git.christophe.jaillet@wanadoo.fr

Merge tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2019-07-13T23:08:36+00:00

Pull powerpc updates from Michael Ellerman:
"Notable changes:

- Removal of the NPU DMA code, used by the out-of-tree Nvidia driver,
as well as some other functions only used by drivers that haven't
(yet?) made it upstream.

- A fix for a bug in our handling of hardware watchpoints (eg. perf
record -e mem: ...) which could lead to register corruption and
kernel crashes.

- Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for
vmalloc when using the Radix MMU.

- A large but incremental rewrite of our exception handling code to
use gas macros rather than multiple levels of nested CPP macros.

And the usual small fixes, cleanups and improvements.

Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab,
Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann,
Athira Rajeev, Cédric Le Goater, Christian Lamparter, Christophe
Leroy, Christophe Lombard, Christoph Hellwig, Daniel Axtens, Denis
Efremov, Enrico Weigelt, Frederic Barrat, Gautham R. Shenoy, Geert
Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg Kurz,
Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro
Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N.
Rao, Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi
Bangoria, Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher
Boessenkool, Shaokun Zhang, Shawn Anastasio, Stewart Smith, Suraj
Jitindar Singh, Thiago Jung Bauermann, YueHaibing"

* tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (163 commits)
powerpc/powernv/idle: Fix restore of SPRN_LDBAR for POWER9 stop state.
powerpc/eeh: Handle hugepages in ioremap space
ocxl: Update for AFU descriptor template version 1.1
powerpc/boot: pass CONFIG options in a simpler and more robust way
powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h
powerpc/irq: Don't WARN continuously in arch_local_irq_restore()
powerpc/module64: Use symbolic instructions names.
powerpc/module32: Use symbolic instructions names.
powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h
powerpc/module64: Fix comment in R_PPC64_ENTRY handling
powerpc/boot: Add lzo support for uImage
powerpc/boot: Add lzma support for uImage
powerpc/boot: don't force gzipped uImage
powerpc/8xx: Add microcode patch to move SMC parameter RAM.
powerpc/8xx: Use IO accessors in microcode programming.
powerpc/8xx: replace #ifdefs by IS_ENABLED() in microcode.c
powerpc/8xx: refactor programming of microcode CPM params.
powerpc/8xx: refactor printing of microcode patch name.
powerpc/8xx: Refactor microcode write
powerpc/8xx: refactor writing of CPM microcode arrays
...

powerpc/pseries: Fix xive=off command line

2019-06-02T09:39:36+00:00

On POWER9, if the hypervisor supports XIVE exploitation mode, the
guest OS will unconditionally requests for the XIVE interrupt mode
even if XIVE was deactivated with the kernel command line xive=off.
Later on, when the spapr XIVE init code handles xive=off, it disables
XIVE and tries to fall back on the legacy mode XICS.

This discrepency causes a kernel panic because the hypervisor is
configured to provide the XIVE interrupt mode to the guest :

  kernel BUG at arch/powerpc/sysdev/xics/xics-common.c:135!
  ...
  NIP xics_smp_probe+0x38/0x98
  LR  xics_smp_probe+0x2c/0x98
  Call Trace:
    xics_smp_probe+0x2c/0x98 (unreliable)
    pSeries_smp_probe+0x40/0xa0
    smp_prepare_cpus+0x62c/0x6ec
    kernel_init_freeable+0x148/0x448
    kernel_init+0x2c/0x148
    ret_from_kernel_thread+0x5c/0x68

Look for xive=off during prom_init and don't ask for XIVE in this
case. One exception though: if the host only supports XIVE, we still
want to boot so we ignore xive=off.

Similarly, have the spapr XIVE init code to looking at the interrupt
mode negotiated during CAS, and ignore xive=off if the hypervisor only
supports XIVE.

Fixes: eac1e731b59e ("powerpc/xive: guest exploitation of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.20
Reported-by: Pavithra R. Prakash 
Signed-off-by: Greg Kurz 
Reviewed-by: Cédric Le Goater 
Signed-off-by: Michael Ellerman

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman

powerpc/xive: prepare all hcalls to support long busy delays

2018-05-10T13:25:10+00:00

This is not the case for the moment, but future releases of pHyp might
need to introduce some synchronisation routines under the hood which
would make the XIVE hcalls longer to complete.

As this was done for H_INT_RESET, let's wrap the other hcalls in a
loop catching the H_LONG_BUSY_* codes.

Signed-off-by: Cédric Le Goater 
Signed-off-by: Michael Ellerman