linux-kernel - Re: [PATCH v2 04/13] arm64: mm: Push __TLBI_VADDR() into __tlbi

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260127113758.00005bea@huawei.com>
Date: Tue, 27 Jan 2026 11:37:58 +0000
From: Jonathan Cameron <jonathan.cameron@...wei.com>
To: Ryan Roberts <ryan.roberts@....com>
CC: Will Deacon <will@...nel.org>, Ard Biesheuvel <ardb@...nel.org>, Catalin
 Marinas <catalin.marinas@....com>, Mark Rutland <mark.rutland@....com>, Linus
 Torvalds <torvalds@...ux-foundation.org>, Oliver Upton
	<oliver.upton@...ux.dev>, Marc Zyngier <maz@...nel.org>, "Dev Jain"
	<dev.jain@....com>, Linu Cherian <Linu.Cherian@....com>,
	<linux-arm-kernel@...ts.infradead.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2 04/13] arm64: mm: Push __TLBI_VADDR() into
 __tlbi_level()

On Mon, 19 Jan 2026 17:21:51 +0000
Ryan Roberts <ryan.roberts@....com> wrote:

> From: Will Deacon <will@...nel.org>
> 
> The __TLBI_VADDR() macro takes an ASID and an address and converts them
> into a single argument formatted correctly for a TLB invalidation
> instruction.
> 
> Rather than have callers worry about this (especially in the case where
> the ASID is zero), push the macro down into __tlbi_level() via a new
> __tlbi_level_asid() helper.
> 
> Signed-off-by: Will Deacon <will@...nel.org>
> Reviewed-by: Linu Cherian <linu.cherian@....com>
> Signed-off-by: Ryan Roberts <ryan.roberts@....com>
One comment inline, but not particularly important given it's
about reducing readability of a workaround a little

Reviewed-by: Jonathan Cameron <jonathan.cameron@...wei.com>

> @@ -674,6 +679,7 @@ static inline bool huge_pmd_needs_flush(pmd_t oldpmd, pmd_t newpmd)
>  #define huge_pmd_needs_flush huge_pmd_needs_flush
>  
>  #undef __tlbi_user
> +#undef __TLBI_VADDR
>  #endif
>  
>  #endif
> diff --git a/arch/arm64/kernel/sys_compat.c b/arch/arm64/kernel/sys_compat.c
> index 4a609e9b65de..ad4857df4830 100644
> --- a/arch/arm64/kernel/sys_compat.c
> +++ b/arch/arm64/kernel/sys_compat.c
> @@ -36,7 +36,7 @@ __do_compat_cache_op(unsigned long start, unsigned long end)
>  			 * The workaround requires an inner-shareable tlbi.
>  			 * We pick the reserved-ASID to minimise the impact.
>  			 */
> -			__tlbi(aside1is, __TLBI_VADDR(0, 0));
> +			__tlbi(aside1is, 0UL);

Dropping the explicit ASID sort of looses some meaning here vs the comment just
above it.  Meh, it's in a work around so most folk will ignore it anyway
if reading this code, so I don't mind that much.

>  			dsb(ish);
>  		}
>