From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Pavel Machek <pavel@denx.de>
Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org,
Catalin Marinas <catalin.marinas@arm.com>,
James Morse <james.morse@arm.com>
Subject: Re: [PATCH 5.16 29/37] arm64: entry: Add vectors that have the bhb mitigation sequences
Date: Fri, 11 Mar 2022 09:15:32 +0100 [thread overview]
Message-ID: <YisFJPSqqWy8GABY@kroah.com> (raw)
In-Reply-To: <20220310232729.GA16308@amd>
On Fri, Mar 11, 2022 at 12:27:29AM +0100, Pavel Machek wrote:
> Hi!
>
> > From: James Morse <james.morse@arm.com>
> >
> > commit ba2689234be92024e5635d30fe744f4853ad97db upstream.
> >
> > Some CPUs affected by Spectre-BHB need a sequence of branches, or a
> > firmware call to be run before any indirect branch. This needs to go
> > in the vectors. No CPU needs both.
> >
> > While this can be patched in, it would run on all CPUs as there is a
> > single set of vectors. If only one part of a big/little combination is
> > affected, the unaffected CPUs have to run the mitigation too.
>
> This adds build error. Same problem is in 5.10.
>
> > --- /dev/null
> > +++ b/arch/arm64/include/asm/vectors.h
> > @@ -0,0 +1,34 @@
> ...
> > +/*
> > + * Note: the order of this enum corresponds to two arrays in entry.S:
> > + * tramp_vecs and __bp_harden_el1_vectors. By default the canonical
> > + * 'full fat' vectors are used directly.
> > + */
> > +enum arm64_bp_harden_el1_vectors {
> > +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
> > + /*
> > + * Perform the BHB loop mitigation, before branching to the canonical
> > + * vectors.
> > + */
> > + EL1_VECTOR_BHB_LOOP,
> > +
> > + /*
> > + * Make the SMC call for firmware mitigation, before branching to the
> > + * canonical vectors.
> > + */
> > + EL1_VECTOR_BHB_FW,
> > +#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
> > +
> > + /*
> > + * Remap the kernel before branching to the canonical vectors.
> > + */
> > + EL1_VECTOR_KPTI,
> > ++};
> > +
>
>
> Note "++". Following patch fixes this up, but it is still a trap for
> people trying to bisect.
Ick, ok, will try to fix up, thanks for finding this.
greg k-h
next prev parent reply other threads:[~2022-03-11 8:15 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-09 16:00 [PATCH 5.16 00/37] 5.16.14-rc1 review Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 01/37] x86/speculation: Rename RETPOLINE_AMD to RETPOLINE_LFENCE Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 02/37] x86/speculation: Add eIBRS + Retpoline options Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 03/37] Documentation/hw-vuln: Update spectre doc Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 04/37] x86/speculation: Include unprivileged eBPF status in Spectre v2 mitigation reporting Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 05/37] x86/speculation: Use generic retpoline by default on AMD Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 06/37] x86/speculation: Update link to AMD speculation whitepaper Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 07/37] x86/speculation: Warn about Spectre v2 LFENCE mitigation Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 08/37] x86/speculation: Warn about eIBRS + LFENCE + Unprivileged eBPF + SMT Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 09/37] ARM: report Spectre v2 status through sysfs Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 10/37] ARM: early traps initialisation Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 11/37] ARM: use LOADADDR() to get load address of sections Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 12/37] ARM: Spectre-BHB workaround Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 13/37] ARM: include unprivileged BPF status in Spectre V2 reporting Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 14/37] arm64: add ID_AA64ISAR2_EL1 sys register Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 15/37] arm64: cpufeature: add HWCAP for FEAT_AFP Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 16/37] arm64: cpufeature: add HWCAP for FEAT_RPRES Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 17/37] arm64: entry.S: Add ventry overflow sanity checks Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 18/37] arm64: spectre: Rename spectre_v4_patch_fw_mitigation_conduit Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 19/37] KVM: arm64: Allow indirect vectors to be used without SPECTRE_V3A Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 20/37] arm64: entry: Make the trampoline cleanup optional Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 21/37] arm64: entry: Free up another register on kptis tramp_exit path Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 22/37] arm64: entry: Move the trampoline data page before the text page Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 23/37] arm64: entry: Allow tramp_alias to access symbols after the 4K boundary Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 24/37] arm64: entry: Dont assume tramp_vectors is the start of the vectors Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 25/37] arm64: entry: Move trampoline macros out of ifdefd section Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 26/37] arm64: entry: Make the kpti trampolines kpti sequence optional Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 27/37] arm64: entry: Allow the trampoline text to occupy multiple pages Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 28/37] arm64: entry: Add non-kpti __bp_harden_el1_vectors for mitigations Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 29/37] arm64: entry: Add vectors that have the bhb mitigation sequences Greg Kroah-Hartman
2022-03-10 23:27 ` Pavel Machek
2022-03-11 8:15 ` Greg Kroah-Hartman [this message]
2022-03-11 8:39 ` Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 30/37] arm64: entry: Add macro for reading symbol addresses from the trampoline Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 31/37] arm64: Add percpu vectors for EL1 Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 32/37] arm64: proton-pack: Report Spectre-BHB vulnerabilities as part of Spectre-v2 Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 33/37] arm64: Mitigate spectre style branch history side channels Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 34/37] KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 35/37] arm64: Use the clearbhb instruction in mitigations Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 36/37] arm64: proton-pack: Include unprivileged eBPF status in Spectre v2 mitigation reporting Greg Kroah-Hartman
2022-03-09 16:00 ` [PATCH 5.16 37/37] ARM: fix build error when BPF_SYSCALL is disabled Greg Kroah-Hartman
2022-03-09 19:05 ` [PATCH 5.16 00/37] 5.16.14-rc1 review Guenter Roeck
2022-03-09 20:01 ` Greg Kroah-Hartman
2022-03-09 21:17 ` Greg Kroah-Hartman
2022-03-09 20:23 ` Shuah Khan
2022-03-09 21:17 ` Daniel Díaz
2022-03-09 21:19 ` Daniel Díaz
2022-03-09 21:49 ` Fox Chen
2022-03-10 10:50 ` Bagas Sanjaya
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