Converting a guest from PV to PV-in-PVH makes the guest to have 384k less memory, which may confuse guest's balloon driver. This happens because Xen unconditionally reserves 640k - 1M region in E820 despite the fact that it's really a usable RAM in PVH boot mode.
Fix this by skipping region type change in virtualised environments, trusting whatever memory map our hypervisor has provided. Signed-off-by: Sergey Dyasli <[email protected]> --- CC: Jan Beulich <[email protected]> CC: Andrew Cooper <[email protected]> CC: Wei Liu <[email protected]> CC: "Roger Pau Monné" <[email protected]> CC: Juergen Gross <[email protected]> --- xen/arch/x86/e820.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/xen/arch/x86/e820.c b/xen/arch/x86/e820.c index 8e8a2c4e1b..30ab8d9b35 100644 --- a/xen/arch/x86/e820.c +++ b/xen/arch/x86/e820.c @@ -318,9 +318,10 @@ static int __init copy_e820_map(struct e820entry * biosmap, unsigned int nr_map) /* * Some BIOSes claim RAM in the 640k - 1M region. - * Not right. Fix it up. + * Not right. Fix it up, but only when running on bare metal. */ - if (type == E820_RAM) { + if ( !cpu_has_hypervisor && type == E820_RAM ) + { if (start < 0x100000ULL && end > 0xA0000ULL) { if (start < 0xA0000ULL) add_memory_region(start, 0xA0000ULL-start, type); -- 2.17.1 _______________________________________________ Xen-devel mailing list [email protected] https://lists.xenproject.org/mailman/listinfo/xen-devel
