From: Richard Henderson <richard.henderson@linaro.org>
To: Catalin Marinas <catalin.marinas@arm.com>,
linux-arm-kernel@lists.infradead.org
Cc: linux-arch@vger.kernel.org,
Richard Earnshaw <Richard.Earnshaw@arm.com>,
Szabolcs Nagy <szabolcs.nagy@arm.com>,
Andrey Konovalov <andreyknvl@google.com>,
Kevin Brodsky <kevin.brodsky@arm.com>,
Peter Collingbourne <pcc@google.com>,
linux-mm@kvack.org, Vincenzo Frascino <vincenzo.frascino@arm.com>,
Will Deacon <will@kernel.org>
Subject: Re: [PATCH v2 19/19] arm64: mte: Add Memory Tagging Extension documentation
Date: Wed, 11 Mar 2020 15:17:54 -0700 [thread overview]
Message-ID: <0857cca0-9f75-398d-e755-f645d2d8a594@linaro.org> (raw)
In-Reply-To: <20200226180526.3272848-20-catalin.marinas@arm.com>
On 2/26/20 10:05 AM, Catalin Marinas wrote:
> + /*
> + * From include/uapi/linux/prctl.h
> + */
> + #define PR_SET_TAGGED_ADDR_CTRL 55
> + #define PR_GET_TAGGED_ADDR_CTRL 56
> + # define PR_TAGGED_ADDR_ENABLE (1UL << 0)
> + # define PR_MTE_TCF_SHIFT 1
> + # define PR_MTE_TCF_NONE (0UL << PR_MTE_TCF_SHIFT)
> + # define PR_MTE_TCF_SYNC (1UL << PR_MTE_TCF_SHIFT)
> + # define PR_MTE_TCF_ASYNC (2UL << PR_MTE_TCF_SHIFT)
> + # define PR_MTE_TCF_MASK (3UL << PR_MTE_TCF_SHIFT)
> + # define PR_MTE_TAG_SHIFT 3
> + # define PR_MTE_TAG_MASK (0xffffUL << PR_MTE_TAG_SHIFT)
Is there a reason not to include TCMA into the set of bits that userland can
control with this prcrl?
I know that ordinarily TCR_ELx requires expensive syncing, but for this
particular field there is a note about "software may change this control bit on
a context switch". Which I take to mean that the usual TLB-related syncing may
be omitted.
r~
next prev parent reply other threads:[~2020-03-11 22:18 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-26 18:05 [PATCH v2 00/19] arm64: Memory Tagging Extension user-space support Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 01/19] arm64: alternative: Allow alternative_insn to always issue the first instruction Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 02/19] arm64: mte: system register definitions Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 03/19] arm64: mte: CPU feature detection and initial sysreg configuration Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 04/19] arm64: mte: Use Normal Tagged attributes for the linear map Catalin Marinas
2020-03-05 16:21 ` Steven Price
2020-03-05 16:38 ` Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 05/19] arm64: mte: Assembler macros and default architecture for .S files Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 06/19] arm64: mte: Tags-aware clear_page() implementation Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 07/19] arm64: mte: Tags-aware copy_page() implementation Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 08/19] arm64: Tags-aware memcmp_pages() implementation Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 09/19] arm64: mte: Add specific SIGSEGV codes Catalin Marinas
2020-02-26 19:05 ` Eric W. Biederman
2020-02-26 19:26 ` Catalin Marinas
2020-02-26 22:33 ` kbuild test robot
2020-02-27 11:05 ` Catalin Marinas
2020-02-27 15:20 ` Eric W. Biederman
2020-02-26 18:05 ` [PATCH v2 10/19] arm64: mte: Handle synchronous and asynchronous tag check faults Catalin Marinas
2020-02-27 11:50 ` Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 11/19] mm: Introduce arch_calc_vm_flag_bits() Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 12/19] arm64: mte: Add PROT_MTE support to mmap() and mprotect() Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 13/19] mm: Introduce arch_validate_flags() Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 14/19] arm64: mte: Validate the PROT_MTE request via arch_validate_flags() Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 15/19] mm: Allow arm64 mmap(PROT_MTE) on RAM-based files Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 16/19] arm64: mte: Allow user control of the tag check mode via prctl() Catalin Marinas
2020-03-09 13:53 ` Kevin Brodsky
2020-02-26 18:05 ` [PATCH v2 17/19] arm64: mte: Allow user control of the generated random tags " Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 18/19] arm64: mte: Kconfig entry Catalin Marinas
2020-02-26 18:05 ` [PATCH v2 19/19] arm64: mte: Add Memory Tagging Extension documentation Catalin Marinas
2020-03-09 14:30 ` Kevin Brodsky
2020-03-11 22:17 ` Richard Henderson [this message]
2020-03-12 9:50 ` Catalin Marinas
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