Commit 1cfd4ccb authored by Jan Beulich's avatar Jan Beulich Committed by Juergen Gross
Browse files

x86/Xen: tidy xen-head.S 



First of all move PV-only ELF notes inside the XEN_PV conditional; note
that
- HV_START_LOW is dropped altogether, as it was meaningful for 32-bit PV
  only,
- the 32-bit instance of VIRT_BASE is dropped, as it would be dead code
  once inside the conditional,
- while PADDR_OFFSET is not exactly unused for PVH, it defaults to zero
  there, and the hypervisor (or tool stack) complains if it is present
  but VIRT_BASE isn't.
Then have the "supported features" note actually report reality: All
three of the features there are supported and/or applicable only in
certain cases.

Signed-off-by: default avatarJan Beulich <jbeulich@suse.com>
Reviewed-by: default avatarJuergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/f99bacc6-2a2f-41b0-5c0b-e01b7051cb07@suse.com


Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
parent fb9b7b4b

arch/x86/xen/xen-head.S

+21 −16
Original line number Diff line number Diff line
@@ -90,30 +90,35 @@ SYM_CODE_END(xen_cpu_bringup_again) 
	ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS,       .asciz "linux")

	ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION,  .asciz "2.6")

	ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION,    .asciz "xen-3.0")

#ifdef CONFIG_X86_32

	ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE,      _ASM_PTR __PAGE_OFFSET)

#else

#ifdef CONFIG_XEN_PV

	ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE,      _ASM_PTR __START_KERNEL_map)

	/* Map the p2m table to a 512GB-aligned user address. */

	ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M,       .quad (PUD_SIZE * PTRS_PER_PUD))

#endif

#ifdef CONFIG_XEN_PV

	ELFNOTE(Xen, XEN_ELFNOTE_ENTRY,          _ASM_PTR startup_xen)

#endif

	ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, _ASM_PTR hypercall_page)

	ELFNOTE(Xen, XEN_ELFNOTE_FEATURES,

		.ascii "!writable_page_tables|pae_pgdir_above_4gb")

	ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES,

		.long (1 << XENFEAT_writable_page_tables) |       \

		      (1 << XENFEAT_dom0) |                       \

		      (1 << XENFEAT_linux_rsdp_unrestricted))

	ELFNOTE(Xen, XEN_ELFNOTE_FEATURES,       .ascii "!writable_page_tables")

	ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE,       .asciz "yes")

	ELFNOTE(Xen, XEN_ELFNOTE_LOADER,         .asciz "generic")

	ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID,

		.quad _PAGE_PRESENT; .quad _PAGE_PRESENT)

	ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCEL, .long 1)

	ELFNOTE(Xen, XEN_ELFNOTE_MOD_START_PFN,  .long 1)

	ELFNOTE(Xen, XEN_ELFNOTE_HV_START_LOW,   _ASM_PTR __HYPERVISOR_VIRT_START)

	ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET,   _ASM_PTR 0)

# define FEATURES_PV (1 << XENFEAT_writable_page_tables)

#else

# define FEATURES_PV 0

#endif

#ifdef CONFIG_XEN_PVH

# define FEATURES_PVH (1 << XENFEAT_linux_rsdp_unrestricted)

#else

# define FEATURES_PVH 0

#endif

#ifdef CONFIG_XEN_DOM0

# define FEATURES_DOM0 (1 << XENFEAT_dom0)

#else

# define FEATURES_DOM0 0

#endif

	ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, _ASM_PTR hypercall_page)

	ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES,

		.long FEATURES_PV | FEATURES_PVH | FEATURES_DOM0)

	ELFNOTE(Xen, XEN_ELFNOTE_LOADER,         .asciz "generic")

	ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCEL, .long 1)



#endif /*CONFIG_XEN */