On Fri, Apr 17, 2020 at 10:01:53AM +0100, Peter Maydell wrote: > On Fri, 17 Apr 2020 at 01:43, Dennis Clarke via <qemu-discuss@nongnu.org> > wrote: > > > > > > Very strange messages from qemu 5.0.0-rc3 wherein I try to run : > > Thanks for the report. Did this work with older QEMU? > > > $ /usr/local/bin/qemu-system-ppc64 --version > > QEMU emulator version 4.2.93 > > Copyright (c) 2003-2020 Fabrice Bellard and the QEMU Project developers > > $ > > $ > > $ /usr/local/bin/qemu-system-ppc64 \ > > > -machine pseries-4.1 -cpu power9 -smp 4 -m 12G -accel tcg \ > > > -drive file=/home/ppc64/ppc64le.qcow2 \ > > > -device virtio-net-pci,netdev=usernet \ > > > -netdev user,id=usernet,hostfwd=tcp::10000-:22 \ > > > -serial stdio -display none -vga none > > qemu-system-ppc64: warning: TCG doesn't support requested feature, > > cap-cfpc=workaround > > qemu-system-ppc64: warning: TCG doesn't support requested feature, > > cap-sbbc=workaround > > qemu-system-ppc64: warning: TCG doesn't support requested feature, > > cap-ibs=workaround > > > > > > SLOF ********************************************************************** > > [kernel boot log snipped] > > > > root@titan:~# > > > > From this point onwards I see an endless stream of : > > > > Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries > > > No idea what that is .. but it doesn't look friendly. > > > > Also I did compile qemu with --enable-debug --disable-strip and the > > performance is truely horrific. I can only assume that those options > > are the cause. Any thoughts from anyone would be wonderful. > > Well, you turned on debug and you got some warnings > which are only emitted with debug on, so you can > work around it by not doing that :-) And yes, debug > is slower (it builds QEMU without optimization enabled > so it's easier to debug QEMU in gdb, and it turns on > various extra sanity checks.) > > The warning is something we should fix -- it's a bug > in the PPC code generation where we didn't correctly > free a TCG temporary. The good news is that this won't > generally have any visible bad effects, because the > TCG common code will clean all those temporaries up > at the end of each block anyway. The only time the leak > is an issue is if guest code has a straight line sequence > of hundreds of the same instruction in a row, in which > case they'll all be in the same block and we might > hit the limit on total temporaries. That won't happen > unless guest code is deliberately doing something crazy. > > David -- is this a known bug?
Not known to me. -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson
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