| Message ID | 1421387106-19101-1-git-send-email-zhugh.fnst@cn.fujitsu.com |
|---|---|
| State | New |
| Headers | show |
Hi all, I am sorry that this method to fix this bug was not perfect. I will find another way to do this. Plz ignore this patch. Regards, Zhu On Fri, 2015-01-16 at 13:45 +0800, Zhu Guihua wrote: > If hot add 100MiB memory like this: > (monitor) object_add memory-backend-ram,id=ram0,size=100M > (monitor) device_add pc-dimm,id=d0,memdev=ram0 > > The hotplug operation will faile, and the guest will print error message: > Section-unaligned hotplug range: start 0x100000000, size 0x6400000 > acpi PNP0C80:00: add_memory failed > acpi PNP0C80:00: acpi_memory_enable_device() error > > Then I found that, according to the func check_hotplug_memory_range() in linux > kernel, backend memory size must be multiple of 128MiB, not 2MiB. > > So this patch checks whether backend memory size is multiple of 128MiB. > > Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> > --- > hw/mem/pc-dimm.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c > index d431834..3b8a015 100644 > --- a/hw/mem/pc-dimm.c > +++ b/hw/mem/pc-dimm.c > @@ -161,9 +161,9 @@ uint64_t pc_dimm_get_free_addr(uint64_t address_space_start, > goto out; > } > > - if (QEMU_ALIGN_UP(size, align) != size) { > + if (QEMU_ALIGN_UP(size, align * 64) != size) { > error_setg(errp, "backend memory size must be multiple of 0x%" > - PRIx64, align); > + PRIx64, align * 64); > goto out; > } >
On Fri, 16 Jan 2015 13:45:06 +0800 Zhu Guihua <zhugh.fnst@cn.fujitsu.com> wrote: > If hot add 100MiB memory like this: > (monitor) object_add memory-backend-ram,id=ram0,size=100M > (monitor) device_add pc-dimm,id=d0,memdev=ram0 > > The hotplug operation will faile, and the guest will print error message: > Section-unaligned hotplug range: start 0x100000000, size 0x6400000 > acpi PNP0C80:00: add_memory failed > acpi PNP0C80:00: acpi_memory_enable_device() error > > Then I found that, according to the func check_hotplug_memory_range() in linux > kernel, backend memory size must be multiple of 128MiB, not 2MiB. It's linux limitation, Windows guests work just fine with small blocks. It should be fixed in linux kernel or/and limitation should be enforced by libvirt/virt-install which knows what type of guest it installs/runs. > > So this patch checks whether backend memory size is multiple of 128MiB. > > Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> > --- > hw/mem/pc-dimm.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c > index d431834..3b8a015 100644 > --- a/hw/mem/pc-dimm.c > +++ b/hw/mem/pc-dimm.c > @@ -161,9 +161,9 @@ uint64_t pc_dimm_get_free_addr(uint64_t address_space_start, > goto out; > } > > - if (QEMU_ALIGN_UP(size, align) != size) { > + if (QEMU_ALIGN_UP(size, align * 64) != size) { > error_setg(errp, "backend memory size must be multiple of 0x%" > - PRIx64, align); > + PRIx64, align * 64); > goto out; > } >
On Mon, 2015-01-19 at 16:55 +0100, Igor Mammedov wrote: > On Fri, 16 Jan 2015 13:45:06 +0800 > Zhu Guihua <zhugh.fnst@cn.fujitsu.com> wrote: > > > If hot add 100MiB memory like this: > > (monitor) object_add memory-backend-ram,id=ram0,size=100M > > (monitor) device_add pc-dimm,id=d0,memdev=ram0 > > > > The hotplug operation will faile, and the guest will print error message: > > Section-unaligned hotplug range: start 0x100000000, size 0x6400000 > > acpi PNP0C80:00: add_memory failed > > acpi PNP0C80:00: acpi_memory_enable_device() error > > > > Then I found that, according to the func check_hotplug_memory_range() in linux > > kernel, backend memory size must be multiple of 128MiB, not 2MiB. > It's linux limitation, Windows guests work just fine with small blocks. > > It should be fixed in linux kernel or/and limitation should be enforced by > libvirt/virt-install which knows what type of guest it installs/runs. > Got it. Thanks for your explanation. Regards, Zhu > > > > So this patch checks whether backend memory size is multiple of 128MiB. > > > > Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> > > --- > > hw/mem/pc-dimm.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c > > index d431834..3b8a015 100644 > > --- a/hw/mem/pc-dimm.c > > +++ b/hw/mem/pc-dimm.c > > @@ -161,9 +161,9 @@ uint64_t pc_dimm_get_free_addr(uint64_t address_space_start, > > goto out; > > } > > > > - if (QEMU_ALIGN_UP(size, align) != size) { > > + if (QEMU_ALIGN_UP(size, align * 64) != size) { > > error_setg(errp, "backend memory size must be multiple of 0x%" > > - PRIx64, align); > > + PRIx64, align * 64); > > goto out; > > } > > >
diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c index d431834..3b8a015 100644 --- a/hw/mem/pc-dimm.c +++ b/hw/mem/pc-dimm.c @@ -161,9 +161,9 @@ uint64_t pc_dimm_get_free_addr(uint64_t address_space_start, goto out; } - if (QEMU_ALIGN_UP(size, align) != size) { + if (QEMU_ALIGN_UP(size, align * 64) != size) { error_setg(errp, "backend memory size must be multiple of 0x%" - PRIx64, align); + PRIx64, align * 64); goto out; }
If hot add 100MiB memory like this: (monitor) object_add memory-backend-ram,id=ram0,size=100M (monitor) device_add pc-dimm,id=d0,memdev=ram0 The hotplug operation will faile, and the guest will print error message: Section-unaligned hotplug range: start 0x100000000, size 0x6400000 acpi PNP0C80:00: add_memory failed acpi PNP0C80:00: acpi_memory_enable_device() error Then I found that, according to the func check_hotplug_memory_range() in linux kernel, backend memory size must be multiple of 128MiB, not 2MiB. So this patch checks whether backend memory size is multiple of 128MiB. Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> --- hw/mem/pc-dimm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)