On Mon, Sep 23, 2019 at 08:29:40AM +0200, Greg Kurz wrote:
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 groug@kaod.org Reviewed-by: Cédric Le Goater clg@kaod.org Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/156821713818.1985334.14123187368108582810.stgit@ba... (cherry picked from commit 6ccb4ac2bf8a35c694ead92f8ac5530a16e8f2c8, 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 groug@kaod.org
This is for 4.14 and 4.19.
Thanks for the backport, now queued up.
greg k-h