From: Catalin Marinas <catalin.marinas@arm.com>
To: Mark Brown <broonie@kernel.org>
Cc: Vincenzo Frascino <Vincenzo.Frascino@arm.com>,
Will Deacon <will@kernel.org>, Kees Cook <keescook@chromium.org>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 04/10] arm64: Set GP bit in kernel page tables to enable BTI for the kernel
Date: Tue, 28 Apr 2020 18:24:32 +0100 [thread overview]
Message-ID: <20200428172432.GB18257@gaia> (raw)
In-Reply-To: <20200415130750.18645-5-broonie@kernel.org>
On Wed, Apr 15, 2020 at 02:07:43PM +0100, Mark Brown wrote:
> diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h
> index 1305e28225fc..7213117ff538 100644
> --- a/arch/arm64/include/asm/pgtable-prot.h
> +++ b/arch/arm64/include/asm/pgtable-prot.h
> @@ -50,7 +53,9 @@ extern bool arm64_use_ng_mappings;
> #define PAGE_KERNEL __pgprot(PROT_NORMAL)
> #define PAGE_KERNEL_RO __pgprot((PROT_NORMAL & ~PTE_WRITE) | PTE_RDONLY)
> #define PAGE_KERNEL_ROX __pgprot((PROT_NORMAL & ~(PTE_WRITE | PTE_PXN)) | PTE_RDONLY)
> +#define PAGE_KERNEL_ROX_GP __pgprot((PROT_NORMAL & ~(PTE_WRITE | PTE_PXN)) | PTE_RDONLY | PTE_GP)
> #define PAGE_KERNEL_EXEC __pgprot(PROT_NORMAL & ~PTE_PXN)
> +#define PAGE_KERNEL_EXEC_GP __pgprot((PROT_NORMAL & ~PTE_PXN) | PTE_GP)
> #define PAGE_KERNEL_EXEC_CONT __pgprot((PROT_NORMAL & ~PTE_PXN) | PTE_CONT)
Are the PAGE_*_GP defines used anywhere in this series?
> diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
> index 9793d3aa9d98..84fea674856f 100644
> --- a/arch/arm64/kernel/cpufeature.c
> +++ b/arch/arm64/kernel/cpufeature.c
> @@ -1800,7 +1800,11 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
> {
> .desc = "Branch Target Identification",
> .capability = ARM64_BTI,
> +#ifdef CONFIG_ARM64_BTI_KERNEL
> + .type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
> +#else
> .type = ARM64_CPUCAP_SYSTEM_FEATURE,
> +#endif
As with PtrAuth, I'm tempted to have a single config for both user and
kernel. Not a strong opinion though, just looking for some consistency.
--
Catalin
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-04-28 17:24 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-15 13:07 [PATCH 00/10] arm64: BTI kernel and vDSO support Mark Brown
2020-04-15 13:07 ` [PATCH 01/10] arm64: kernel: Convert to modern annotations for assembly functions Mark Brown
2020-04-15 13:07 ` [PATCH 02/10] arm64: bti: Support building kernel C code using BTI Mark Brown
2020-04-15 13:07 ` [PATCH 03/10] arm64: asm: Override SYM_FUNC_START when building the kernel with BTI Mark Brown
2020-04-15 13:07 ` [PATCH 04/10] arm64: Set GP bit in kernel page tables to enable BTI for the kernel Mark Brown
2020-04-28 17:24 ` Catalin Marinas [this message]
2020-04-28 18:03 ` Mark Brown
2020-04-29 7:40 ` Will Deacon
2020-04-29 10:10 ` Mark Brown
2020-04-15 13:07 ` [PATCH 05/10] arm64: mm: Mark module text as guarded pages Mark Brown
2020-04-27 15:07 ` Mark Brown
2020-04-15 13:07 ` [PATCH 06/10] arm64: bti: Provide Kconfig for kernel mode BTI Mark Brown
2020-04-15 13:07 ` [PATCH 07/10] arm64: asm: Provide a mechanism for generating ELF note for BTI Mark Brown
2020-04-15 13:07 ` [PATCH 08/10] arm64: vdso: Annotate " Mark Brown
2020-04-15 13:07 ` [PATCH 09/10] arm64: vdso: Force the vDSO to be linked as BTI when built " Mark Brown
2020-04-15 13:07 ` [PATCH 10/10] arm64: vdso: Map the vDSO text with guarded pages " Mark Brown
2020-04-15 13:07 ` [PATCH 10/10] arm64: vdso: Map the VDSO " Mark Brown
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200428172432.GB18257@gaia \
--to=catalin.marinas@arm.com \
--cc=Vincenzo.Frascino@arm.com \
--cc=broonie@kernel.org \
--cc=keescook@chromium.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).