From: Ian Campbell Date: Tue, 6 Oct 2015 08:42:35 +0000 (+0100) Subject: docs: xl.cfg: permissive option is not PV only. X-Git-Tag: 4.7.0-rc1~1261 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=7f25baba1c0942e50757f4ecb233202dbbc057b9;p=xen.git docs: xl.cfg: permissive option is not PV only. Since XSA-131 qemu-xen has defaulted to non-permissive mode and the option was extended to cover that case in 015a373351e5 "tools: libxl: allow permissive qemu-upstream pci passthrough". Since I was rewrapping to adjust the text anyway I've split the safety warning into a separate paragraph to make it more obvious. Signed-off-by: Ian Campbell Cc: Eric Acked-by: Wei Liu --- diff --git a/docs/man/xl.cfg.pod.5 b/docs/man/xl.cfg.pod.5 index f8fa48f7aa..b63846a6a6 100644 --- a/docs/man/xl.cfg.pod.5 +++ b/docs/man/xl.cfg.pod.5 @@ -752,14 +752,17 @@ Possible Bs are: =item B -(PV only) By default pciback only allows PV guests to write "known -safe" values into PCI config space. But many devices require writes -to other areas of config space in order to operate properly. This -tells the pciback driver to allow all writes to PCI config space of -this device by this domain. This option should be enabled with -caution: it gives the guest much more control over the device, which -may have security or stability implications. It is recommended to -enable this option only for trusted VMs under administrator control. +By default pciback only allows PV guests to write "known safe" values +into PCI config space, likewise QEMU (both qemu-xen and +qemu-traditional) imposes the same contraint on HVM guests. However +many devices require writes to other areas of config space in order to +operate properly. This option tells the backend (pciback or QEMU) to +allow all writes to PCI config space of this device by this domain. + +This option should be enabled with caution: it gives the guest much +more control over the device, which may have security or stability +implications. It is recommended to enable this option only for +trusted VMs under administrator control. =item B @@ -798,9 +801,8 @@ Note this would override global B option. =item B -(PV only) Changes the default value of 'permissive' for all PCI -devices passed through to this VM. See L -above. +Changes the default value of 'permissive' for all PCI devices passed +through to this VM. See L above. =item B