linux-stable.git/arch/powerpc/sysdev/xive/native.c, branch v4.14.331

powerpc/xive: Ignore kmemleak false positives

2020-09-03T09:22:24+00:00

[ Upstream commit f0993c839e95dd6c7f054a1015e693c87e33e4fb ]

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
Signed-off-by: Sasha Levin

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

2020-04-24T06:00:46+00:00

commit b1a504a6500df50e83b701b7946b34fce27ad8a3 upstream.

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
Signed-off-by: Greg Kroah-Hartman

powerpc/xive: Fix bogus error code returned by OPAL

2019-10-05T10:47:32+00:00

commit 6ccb4ac2bf8a35c694ead92f8ac5530a16e8f2c8 upstream.

There's a bug in skiboot that causes the OPAL_XIVE_ALLOCATE_IRQ call
to return the 32-bit value 0xffffffff when OPAL has run out of IRQs.
Unfortunatelty, OPAL return values are signed 64-bit entities and
errors are supposed to be negative. If that happens, the linux code
confusingly treats 0xffffffff as a valid IRQ number and panics at some
point.

A fix was recently merged in skiboot:

e97391ae2bb5 ("xive: fix return value of opal_xive_allocate_irq()")

but we need a workaround anyway to support older skiboots already
in the field.

Internally convert 0xffffffff to OPAL_RESOURCE which is the usual error
returned upon resource exhaustion.

Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Greg Kurz 
Reviewed-by: Cédric Le Goater 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/156821713818.1985334.14123187368108582810.stgit@bahia.lan
(groug: fix arch/powerpc/platforms/powernv/opal-wrappers.S instead of
        non-existing arch/powerpc/platforms/powernv/opal-call.c)
Signed-off-by: Greg Kurz 
Signed-off-by: Greg Kroah-Hartman

powerpc/xive: Fix trying to "push" an already active pool VP

2018-04-24T07:36:37+00:00

commit b32e56e5a87a1f9243db92bc7a5df0ffb4627cfb upstream.

When setting up a CPU, we "push" (activate) a pool VP for it.

However it's an error to do so if it already has an active
pool VP.

This happens when doing soft CPU hotplug on powernv since we
don't tear down the CPU on unplug. The HW flags the error which
gets captured by the diagnostics.

Fix this by making sure to "pull" out any already active pool
first.

Fixes: 243e25112d06 ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

treewide: make "nr_cpu_ids" unsigned

2017-09-09T01:26:48+00:00

First, number of CPUs can't be negative number.

Second, different signnnedness leads to suboptimal code in the following
cases:

1)
	kmalloc(nr_cpu_ids * sizeof(X));

"int" has to be sign extended to size_t.

2)
	while (loff_t *pos < nr_cpu_ids)

MOVSXD is 1 byte longed than the same MOV.

Other cases exist as well. Basically compiler is told that nr_cpu_ids
can't be negative which can't be deduced if it is "int".

Code savings on allyesconfig kernel: -3KB

	add/remove: 0/0 grow/shrink: 25/264 up/down: 261/-3631 (-3370)
	function                                     old     new   delta
	coretemp_cpu_online                          450     512     +62
	rcu_init_one                                1234    1272     +38
	pci_device_probe                             374     399     +25

				...

	pgdat_reclaimable_pages                      628     556     -72
	select_fallback_rq                           446     369     -77
	task_numa_find_cpu                          1923    1807    -116

Link: http://lkml.kernel.org/r/20170819114959.GA30580@avx2
Signed-off-by: Alexey Dobriyan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

powerpc/xive: add the HW IRQ number under xive_irq_data

2017-09-02T11:02:37+00:00

It will be required later by the H_INT_ESB hcall.

Signed-off-by: Cédric Le Goater 
Acked-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman

powerpc/xive: introduce a common routine xive_queue_page_alloc()

2017-09-02T11:02:34+00:00

This routine will be used in the spapr backend. Also introduce a short
xive_alloc_order() helper.

Signed-off-by: Cédric Le Goater 
Reviewed-by: David Gibson 
Acked-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman

powerpc: Convert to using %pOF instead of full_name

2017-08-23T12:27:04+00:00

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: Anatolij Gustschin 
Cc: Scott Wood 
Cc: Kumar Gala 
Cc: Arnd Bergmann 
Cc: linuxppc-dev@lists.ozlabs.org
Reviewed-by: Tyrel Datwyler 
Signed-off-by: Michael Ellerman

powerpc/xive: Fix section mismatch warnings

2017-08-10T13:41:02+00:00

Both xive_core_init() and xive_native_init() are called from and call
__init routines, so they should also be __init.

Signed-off-by: Michael Ellerman

powerpc/xive: Silence message about VP block allocation

2017-06-28T03:08:08+00:00

There is no reason for that message to be pr_info(), it will be printed
every time we start a KVM guest.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman