On Wed, Dec 08, 2010 at 04:27:45PM -0200, Luiz Capitulino wrote: > On Wed, 08 Dec 2010 12:23:12 -0600 > Anthony Liguori <aligu...@linux.vnet.ibm.com> wrote: > > > On 12/08/2010 12:01 PM, Luiz Capitulino wrote: > > > Currently, x86_64-softmmu qemu segfaults when trying to use> 4095M > > > memsize. > > > This patch adds a simple check and error message (much like the 2047 > > > limit on > > > 32-bit hosts) on ram_size in the control path after we determine we're > > > not using kvm > > > > > > Upstream qemu-kvm is affected if using the -no-kvm option; this patch > > > address > > > the segfault there as well. > > > > > > Signed-off-by: Ryan Harper<ry...@us.ibm.com> > > > Signed-off-by: Aurelien Jarno<aurel...@aurel32.net> > > > --- > > > NOTE: this patch was applied in the v0.12.x branch, but it seems it got > > > lost for master > > > > > > > No, it was intentional. We should fix the segv, this is not a known > > limitation but rather a bug. > > A TCG bug, I presume? >
Do you have more details about this issue and how to reproduce it? Support for more than 4GB of memory has been added a few years ago, and I am not able to reproduce the problem anymore (I have booted a 64-bit guest with 6GB of RAM, and make sure the guest use the whole memory). I guess TCG itself is fine, but there might be a bug in the MMU emulation in some cases. I also noticed that now i386-softmmu has been artificially limited to 2047MB. Tthis configuration used to support up to 64GB of RAM (PAE) on 64-bit hosts. -- Aurelien Jarno GPG: 1024D/F1BCDB73 aurel...@aurel32.net http://www.aurel33.net
