• Boris Ostrovsky's avatar
    xen/pvh: Indicate XENFEAT_linux_rsdp_unrestricted to Xen · a5a18ae7
    Boris Ostrovsky authored
    Pre-4.17 kernels ignored start_info's rsdp_paddr pointer and instead
    relied on finding RSDP in standard location in BIOS RO memory. This
    has worked since that's where Xen used to place it.
    
    However, with recent Xen change (commit 4a5733771e6f ("libxl: put RSDP
    for PVH guest near 4GB")) it prefers to keep RSDP at a "non-standard"
    address. Even though as of commit b17d9d1d ("x86/xen: Add pvh
    specific rsdp address retrieval function") Linux is able to find RSDP,
    for back-compatibility reasons we need to indicate to Xen that we can
    handle this, an we do so by setting XENFEAT_linux_rsdp_unrestricted
    flag in ELF notes.
    
    (Also take this opportunity and sync features.h header file with Xen)
    Signed-off-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
    Reviewed-by: default avatarJuergen Gross <jgross@suse.com>
    Reviewed-by: default avatarWei Liu <wei.liu2@citrix.com>
    a5a18ae7
xen-head.S 2.94 KB