[SeaBIOS] [Qemu-devel] [RESEND PATCH v3] hotplug: add device per func in ACPI DSDT tables

[Amos Kong]

----- Original Message -----
> On Wed, 2012-05-09 at 15:24 +0800, Amos Kong wrote:
> > Boot up a Linux VM with 8 pci block devices which
> > are the 8 functions in one pci slot.
> > | # qemu-kvm ...
> > | -drive file=images/u0,if=none,id=drv0,format=qcow2,cache=none \
> > | -device
> > | virtio-blk-pci,drive=drv0,id=v0,multifunction=on,addr=0x03.0 \
> > | ....
> > | -drive file=images/u7,if=none,id=drv7,format=qcow2,cache=none \
> > | -device
> > | virtio-blk-pci,drive=drv7,id=v7,multifunction=on,addr=0x03.7 \
> > 
> > Check devices in guest.
> > | vm)# ls /dev/vd*
> > |    vda vdb vdc vde vdf vdg vdh
> > | vm)# lspci |grep block
> > | 00:03.0 SCSI storage controller: Red Hat, Inc Virtio block device
> > |    ...
> > | 00:03.7 SCSI storage controller: Red Hat, Inc Virtio block device
> > |
> > 
> > Func1~7 still exist in guest after hot-removing the whole slot
> > through qemu monitor.
> > | vm)# lspci |grep block    (00:03.0 disappeared)
> > | 00:03.1 SCSI storage controller: Red Hat, Inc Virtio block device
> > | (rev ff)
> > |    ...
> > | 00:03.7 SCSI storage controller: Red Hat, Inc Virtio block device
> > | (rev ff)
> > | vm)# ls /dev/vd*          (vda disappeared)
> > |    vdb vdc vde vdf vdg vdh
> > | vm)# mkfs /dev/vdb
> > |    INFO: task mkfs.ext2:1784 blocked for more than 120 seconds.
> > |    (task hung)
> > 
> > 
> > Currently only func0 is defined in ACPI DSDT table
> > of seabios, and only hot-adding func0 would cause
> > a ACPI event for notification. Other funcs except
> > func0 wouldn't be registered in linux pci driver.
> > (we can only found func0 in slot->funcs list of
> > pci driver).
> > 
> > When VM pci driver receives an ACPI event for
> > hot-removing, it will only clean functions in
> > slot->funcs list, the other funcs could not be
> > cleaned.
> > 
> > This patch adds device per function in ACPI DSDT tables,
> > then all funcs will be registered in slot->funcs list.
> > It's coincident with microsoft's example:
> > http://www.microsoft.com/china/whdc/system/pnppwr/hotadd/hotplugpci.mspx#EUH
> > 
> > Have tested with linux/winxp/win7, hot-adding/hot-remving,
> > single/multiple function devices, they are all fine(all
> > added devices can be removed).
> > 
> > This patch includes some bits mst wrote, thanks!
> > ---
> > old discussion: http://marc.info/?l=kvm&m=132428400917405&w=2
> > 
> > Signed-off-by: Amos Kong <akong at redhat.com>
> > CC: Michael S. Tsirkin <mst at redhat.com>
> > ---
> >  src/ssdt-pcihp.dsl |   17
> >  src/ssdt-pcihp.hex | 8869
> >  +++++++++++++++++++++++++++++++++++++++++++++++++++-
> >  2 files changed, 8781 insertions(+), 105 deletions(-)
> > 
> > diff --git a/src/ssdt-pcihp.dsl b/src/ssdt-pcihp.dsl
> > index 4b435b8..2a3c326 100644
> > --- a/src/ssdt-pcihp.dsl
> > +++ b/src/ssdt-pcihp.dsl
> > @@ -17,14 +17,23 @@ DefinitionBlock ("ssdt-pcihp.aml", "SSDT",
> > 0x01, "BXPC", "BXSSDTPCIHP", 0x1)
> >          // at runtime, if the slot is detected to not support
> >          hotplug.
> >          // Extract the offset of the address dword and the
> >          // _EJ0 name to allow this patching.
> > -#define hotplug_slot(slot)                              \
> > -        Device (S##slot) {                              \
> > +#define hotplug_func(slot, fn)                          \
> > +        Device (S##slot##fn) {                          \
> >             ACPI_EXTRACT_NAME_DWORD_CONST aml_adr_dword  \
> > -           Name (_ADR, 0x##slot##0000)                  \
> 
> I would have guessed it to be sufficient to change _ADR to
> 0x##slot##ffff, does that not work?


No, changing this to "0x##slot##ffff" doesn't resolve the bug.
(tested)

I'm trying to fix this problem in guest pci driver.
http://marc.info/?l=linux-pci&m=133657729118731&w=2


Thanks, Amos

> 
> > +           Name (_ADR, 0x##slot##000##fn)               \
> >             ACPI_EXTRACT_METHOD_STRING aml_ej0_name      \
> >             Method (_EJ0, 1) { Return(PCEJ(0x##slot)) }  \
> >             Name (_SUN, 0x##slot)                        \
> >          }
> > +#define hotplug_slot(slot)     \
> > +        hotplug_func(slot, 0)  \
> > +        hotplug_func(slot, 1)  \
> > +        hotplug_func(slot, 2)  \
> > +        hotplug_func(slot, 3)  \
> > +        hotplug_func(slot, 4)  \
> > +        hotplug_func(slot, 5)  \
> > +        hotplug_func(slot, 6)  \
> > +        hotplug_func(slot, 7)
> >  
> >          hotplug_slot(01)
> >          hotplug_slot(02)
> > @@ -59,7 +68,7 @@ DefinitionBlock ("ssdt-pcihp.aml", "SSDT", 0x01,
> > "BXPC", "BXSSDTPCIHP", 0x1)
> >          hotplug_slot(1f)
> >  
> >  #define gen_pci_hotplug(slot)   \
> > -            If (LEqual(Arg0, 0x##slot)) { Notify(S##slot, Arg1) }
> > +            If (LEqual(Arg0, 0x##slot)) { Notify(S##slot##0, Arg1)
> > }
> >  
> >          Method(PCNT, 2) {
> >              gen_pci_hotplug(01)
> 
> 
> 
>