On Fri, Sep 08, 2017 at 06:39:01PM +0300, Michael S. Tsirkin wrote: > On Mon, Aug 07, 2017 at 08:16:13PM +0200, Marc-André Lureau wrote: > > diff --git a/docs/specs/fw_cfg.txt b/docs/specs/fw_cfg.txt > > index 08c00bdf44..37d0f9f40a 100644 > > --- a/docs/specs/fw_cfg.txt > > +++ b/docs/specs/fw_cfg.txt > > @@ -136,6 +136,22 @@ struct FWCfgFile { /* an individual file > > entry, 64 bytes total */ > > char name[56]; /* fw_cfg item name, NUL-terminated ascii */ > > }; > > > > +=== etc/vmcoreinfo === > > + > > +A guest may use this entry to add information details to qemu > > +dumps. The entry gives location and size of an ELF note that is > > +appended in qemu dumps. > > + > > +The entry is of 12 bytes with this format: > > + > > +struct FWCfgVMCoreInfo { > > + uint64_t paddr; /* physical address of ELF note, LE */ > > + uint32_t size; /* size of ELF note region, LE */ > > +}; > > + > > +The note format/class must be of the target bitness and the size must > > +be less than 1Mb. > > + > > I would say adding a format bitmap would make sense for future compatibility. > How about: > > struct FWCfgVMCoreInfo { > uint16_t host_format; /* Formats host supports. 0x1 LE - ELF note. > Other bits - ignored. */ > uint16_t guest_format; /* Formats guest supplies. Must be 0x1 LE */
.. to set the ELF note info, or 0x0 to reset the device. > uint32_t size; /* size of ELF note region, LE */ > uint64_t paddr; /* physical address of ELF note, LE */ > }; > > > > === All Other Data Items === > > > > Please consult the QEMU source for the most up-to-date and authoritative > > list > > -- > > 2.14.0.1.geff633fa0