Occasionally in Linux guests on x86_64 we're seeing logs like:
ppc_set_irq: 0x55b4e0d562f0 n_IRQ 8 level 1 => pending 00000100req 00000004
when they should read:
ppc_set_irq: 0x55b4e0d562f0 n_IRQ 8 level 1 => pending 00000100req 00000002
The "00000004" is CPU_INTERRUPT_EXITTB yet the code calls
cpu_interrupt(cs, CPU_INTERRUPT_HARD) ("00000002") in this function
just before the log message. Something is causing the HARD bit setting
to get lost.
The knock on effect of losing that bit is the decrementer timer interrupts
don't get delivered which causes the guest to sit idle in its idle handler
and 'hang'.
The issue occurs due to races from code which sets CPU_INTERRUPT_EXITTB.
Rather than poking directly into cs->interrupt_request, that code needs to:
a) hold BQL
b) use the cpu_interrupt() helper
This patch fixes the call sites to do this, fixing the hang. The calls
are made from a variety of contexts so a helper function is added to handle
the necessary locking. This can likely be improved and optimised in the future
but it ensures the code is correct and doesn't lockup as it stands today.
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
We have never has the concept of global TLB entries which would avoid
the flush so we never actually use this flag. Drop it and make clear
that tlb_flush is the sledge-hammer it has always been.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
[DG: ppc portions]
Acked-by: David Gibson <david@gibson.dropbear.id.au>
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.
Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [crisµblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
