Date:   Tue, 11 Jan 2022 13:11:11 +1000
From:   Nicholas Piggin <npiggin@gmail.com>
Subject: Re: [PATCH] powerpc/time: Fix build failure due to
 do_hard_irq_enable() on PPC32
To:     Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Paul Mackerras <paulus@samba.org>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>
References: <247e01e0e10f4dbc59b5ff89e81702eb1ee7641e.1641828571.git.christophe.leroy@csgroup.eu>
In-Reply-To: <247e01e0e10f4dbc59b5ff89e81702eb1ee7641e.1641828571.git.christophe.leroy@csgroup.eu>
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Excerpts from Christophe Leroy's message of January 11, 2022 1:29 am:
> 	  CC      arch/powerpc/kernel/time.o
> 	In file included from <command-line>:
> 	./arch/powerpc/include/asm/hw_irq.h: In function 'do_hard_irq_enable':
> 	././include/linux/compiler_types.h:335:45: error: call to '__compiletime=
_assert_35' declared with attribute error: BUILD_BUG failed
> 	  335 |         _compiletime_assert(condition, msg, __compiletime_assert=
_, __COUNTER__)
> 	      |                                             ^
> 	././include/linux/compiler_types.h:316:25: note: in definition of macro =
'__compiletime_assert'
> 	  316 |                         prefix ## suffix();                     =
        \
> 	      |                         ^~~~~~
> 	././include/linux/compiler_types.h:335:9: note: in expansion of macro '_=
compiletime_assert'
> 	  335 |         _compiletime_assert(condition, msg, __compiletime_assert=
_, __COUNTER__)
> 	      |         ^~~~~~~~~~~~~~~~~~~
> 	./include/linux/build_bug.h:39:37: note: in expansion of macro 'compilet=
ime_assert'
> 	   39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), =
msg)
> 	      |                                     ^~~~~~~~~~~~~~~~~~
> 	./include/linux/build_bug.h:59:21: note: in expansion of macro 'BUILD_BU=
G_ON_MSG'
> 	   59 | #define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed")
> 	      |                     ^~~~~~~~~~~~~~~~
> 	./arch/powerpc/include/asm/hw_irq.h:483:9: note: in expansion of macro '=
BUILD_BUG'
> 	  483 |         BUILD_BUG();
> 	      |         ^~~~~~~~~
>=20
> should_hard_irq_enable() returns false on PPC32 so this BUILD_BUG() shoul=
dn't trigger.
>=20
> Force inlining of should_hard_irq_enable()
>=20
> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> Fixes: 0faf20a1ad16 ("powerpc/64s/interrupt: Don't enable MSR[EE] in irq =
handlers unless perf is in use")
> Cc: Nicholas Piggin <npiggin@gmail.com>

Acked-by: Nicholas Piggin <npiggin@gmail.com>

Thanks,
Nick

> ---
>  arch/powerpc/include/asm/hw_irq.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>=20
> diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm=
/hw_irq.h
> index a58fb4aa6c81..674e5aaafcbd 100644
> --- a/arch/powerpc/include/asm/hw_irq.h
> +++ b/arch/powerpc/include/asm/hw_irq.h
> @@ -473,7 +473,7 @@ static inline bool arch_irq_disabled_regs(struct pt_r=
egs *regs)
>  	return !(regs->msr & MSR_EE);
>  }
> =20
> -static inline bool should_hard_irq_enable(void)
> +static __always_inline bool should_hard_irq_enable(void)
>  {
>  	return false;
>  }
> --=20
> 2.33.1
>=20