Re: [tip: x86/urgent] x86/entry/32: Fix XEN_PV build dependency

[Andy Lutomirski]

> On Jul 5, 2020, at 12:44 PM, tip-bot2 for Ingo Molnar <tip-bot2@xxxxxxxxxxxxx> wrote:
> 
> ïThe following commit has been merged into the x86/urgent branch of tip:
> 
> Commit-ID:     a4c0e91d1d65bc58f928b80ed824e10e165da22c
> Gitweb:        https://git.kernel.org/tip/a4c0e91d1d65bc58f928b80ed824e10e165da22c
> Author:        Ingo Molnar <mingo@xxxxxxxxxx>
> AuthorDate:    Sun, 05 Jul 2020 21:33:11 +02:00
> Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
> CommitterDate: Sun, 05 Jul 2020 21:39:23 +02:00
> 
> x86/entry/32: Fix XEN_PV build dependency
> 
> xenpv_exc_nmi() and xenpv_exc_debug() are only defined on 64-bit kernels,
> but they snuck into the 32-bit build via <asm/identry.h>, causing the link
> to fail:
> 
>  ld: arch/x86/entry/entry_32.o: in function `asm_xenpv_exc_nmi':
>  (.entry.text+0x817): undefined reference to `xenpv_exc_nmi'
> 
>  ld: arch/x86/entry/entry_32.o: in function `asm_xenpv_exc_debug':
>  (.entry.text+0x827): undefined reference to `xenpv_exc_debug'
> 
> Only use them on 64-bit kernels.

JÃrgen, can you queue a revert for when PV32 goes away?

> 
> Fixes: f41f0824224e: ("x86/entry/xen: Route #DB correctly on Xen PV")
> Cc: Andy Lutomirski <luto@xxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
> ---
> arch/x86/include/asm/idtentry.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
> index eeac6dc..f3d7083 100644
> --- a/arch/x86/include/asm/idtentry.h
> +++ b/arch/x86/include/asm/idtentry.h
> @@ -553,7 +553,7 @@ DECLARE_IDTENTRY_RAW(X86_TRAP_MC,    exc_machine_check);
> 
> /* NMI */
> DECLARE_IDTENTRY_NMI(X86_TRAP_NMI,    exc_nmi);
> -#ifdef CONFIG_XEN_PV
> +#if defined(CONFIG_XEN_PV) && defined(CONFIG_X86_64)
> DECLARE_IDTENTRY_RAW(X86_TRAP_NMI,    xenpv_exc_nmi);
> #endif
> 
> @@ -563,7 +563,7 @@ DECLARE_IDTENTRY_DEBUG(X86_TRAP_DB,    exc_debug);
> #else
> DECLARE_IDTENTRY_RAW(X86_TRAP_DB,    exc_debug);
> #endif
> -#ifdef CONFIG_XEN_PV
> +#if defined(CONFIG_XEN_PV) && defined(CONFIG_X86_64)
> DECLARE_IDTENTRY_RAW(X86_TRAP_DB,    xenpv_exc_debug);
> #endif
>