From: Dave Hansen <dave.hansen@intel.com>
To: Fenghua Yu <fenghua.yu@intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, H Peter Anvin <hpa@zytor.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Ashok Raj <ashok.raj@intel.com>,
Peter Zijlstra <peterz@infradead.org>,
Xiaoyao Li <xiaoyao.li@intel.com>,
Michael Chan <michael.chan@broadcom.com>,
Ravi V Shankar <ravi.v.shankar@intel.com>
Cc: linux-kernel <linux-kernel@vger.kernel.org>, x86 <x86@kernel.org>,
linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
kvm@vger.kernel.org
Subject: Re: [PATCH v5 09/18] x86/split_lock: Handle #AC exception for split lock
Date: Tue, 12 Mar 2019 16:51:22 -0700 [thread overview]
Message-ID: <5c76062a-e088-fdb3-09e2-7e4423d820a1@intel.com> (raw)
In-Reply-To: <1552431636-31511-10-git-send-email-fenghua.yu@intel.com>
On 3/12/19 4:00 PM, Fenghua Yu wrote:
> +#ifndef CONFIG_CPU_SUP_INTEL
> DO_ERROR(X86_TRAP_AC, SIGBUS, BUS_ADRALN, NULL, "alignment check", alignment_check)
> +#else
> +dotraplinkage void do_alignment_check(struct pt_regs *regs, long error_code)
> +{
> + unsigned int trapnr = X86_TRAP_AC;
> + char str[] = "alignment check";
> + int signr = SIGBUS;
> +
> + RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
> +
> + if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) !=
> + NOTIFY_STOP) {
> + cond_local_irq_enable(regs);
> + if (!user_mode(regs)) {
> + /*
> + * Only split lock can generate #AC from kernel. Warn
> + * and disable #AC for split lock on current CPU.
> + */
> + msr_clear_bit(MSR_TEST_CTL,
> + TEST_CTL_ENABLE_SPLIT_LOCK_DETECT_SHIFT)
I don't see any feature checking here. Don't we need to see if this MSR
is supported?
Shouldn't the code here on systems that don't support split lock
disabling be the same as on CONFIG_CPU_SUP_INTEL=n systems?
> + WARN_ONCE(1, "A split lock issue is detected.\n");
> +
> + return;
> + }
> + /* Handle #AC generated from user code. */
> + do_trap(X86_TRAP_AC, SIGBUS, "alignment check", regs,
> + error_code, BUS_ADRALN, NULL);
> + }
> +}
> +#endif
So... Do we really need an Intel-specific #ifdef for this sucker?
next prev parent reply other threads:[~2019-03-12 23:51 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-12 23:00 [PATCH v5 00/18] x86/split_lock: Enable #AC exception for split locked accesses Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 01/18] x86/common: Align cpu_caps_cleared and cpu_caps_set to unsigned long Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 02/18] drivers/net/b44: Align pwol_mask to unsigned long for better performance Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 03/18] wlcore: simplify/fix/optimize reg_ch_conf_pending operations Fenghua Yu
2019-03-14 13:16 ` Kalle Valo
2019-03-14 23:16 ` Fenghua Yu
2019-03-15 17:17 ` Paolo Bonzini
2019-03-26 7:55 ` Kalle Valo
2019-03-12 23:00 ` [PATCH v5 04/18] x86/split_lock: Align x86_capability to unsigned long to avoid split locked access Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 05/18] x86/cpufeatures: Enumerate IA32_CORE_CAPABILITIES MSR Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 06/18] x86/msr-index: Define IA32_CORE_CAPABILITY MSR and #AC exception for split lock bit Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 07/18] x86/split_lock: Enumerate #AC for split lock by MSR IA32_CORE_CAPABILITY Fenghua Yu
2019-03-12 23:52 ` Dave Hansen
2019-03-13 0:56 ` Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 08/18] x86/split_lock: Define MSR TEST_CTL register Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 09/18] x86/split_lock: Handle #AC exception for split lock Fenghua Yu
2019-03-12 23:51 ` Dave Hansen [this message]
2019-03-13 0:49 ` Fenghua Yu
2019-03-13 16:22 ` Dave Hansen
2019-03-12 23:00 ` [PATCH v5 10/18] kvm/x86: Emulate MSR IA32_CORE_CAPABILITY Fenghua Yu
2019-03-13 8:15 ` Paolo Bonzini
2019-03-12 23:00 ` [PATCH v5 11/18] kvm/vmx: Emulate MSR TEST_CTL Fenghua Yu
2019-03-13 8:15 ` Paolo Bonzini
2019-03-12 23:00 ` [PATCH v5 12/18] x86/split_lock: Enable #AC for split lock by default Fenghua Yu
2019-03-12 23:43 ` Dave Hansen
2019-03-12 23:00 ` [PATCH v5 13/18] x86/split_lock: Add a sysfs interface to allow user to enable or disable split lock detection on all CPUs during run time Fenghua Yu
2019-03-12 23:48 ` Dave Hansen
2019-03-13 0:53 ` Fenghua Yu
2019-03-13 1:08 ` Dave Hansen
2019-03-12 23:00 ` [PATCH v5 14/18] x86/clearcpuid: Support multiple clearcpuid options Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 15/18] x86/clearcpuid: Support feature flag string in kernel option clearcpuid Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 16/18] x86/clearcpuid: Apply cleared feature bits that are forced set before Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 17/18] x86/clearcpuid: Clear CPUID bit in CPUID faulting Fenghua Yu
2019-03-12 23:00 ` [PATCH v5 18/18] Change document for kernel option clearcpuid Fenghua Yu
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=5c76062a-e088-fdb3-09e2-7e4423d820a1@intel.com \
--to=dave.hansen@intel.com \
--cc=ashok.raj@intel.com \
--cc=fenghua.yu@intel.com \
--cc=hpa@zytor.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-wireless@vger.kernel.org \
--cc=michael.chan@broadcom.com \
--cc=mingo@redhat.com \
--cc=netdev@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=peterz@infradead.org \
--cc=ravi.v.shankar@intel.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
--cc=xiaoyao.li@intel.com \
/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).