linux-kernel - gic_write_grpen1 in hotplug flow

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-next>] [day] [month] [year] [list]

Message-ID: <5e16d564fc1f3482d9ee15a5a1df4265@codeaurora.org>
Date:   Wed, 03 May 2017 18:30:04 -0700
From:   Sodagudi Prasad <psodagud@...eaurora.org>
To:     marc.zyngier@....com, sudeep.holla@....com, will.deacon@....com
Cc:     Jason Cooper <jason@...edaemon.net>,
        Thomas Gleixner <tglx@...utronix.de>,
        linux-kernel@...r.kernel.org
Subject: gic_write_grpen1 in hotplug flow

Hi All,

This is regarding the usage of gic_write_grpen1 API usage in irq-gic-v3 
driver.

Here my understanding about ICC_IGRPEN1_EL1.
ICC_IGRPEN1_EL1 is banked between secure and non-secure states. If two 
secure states are implemented, Secure side Group bit is set by the 
platform firmware (PSCI) and kernel need to set in non secure state.
https://mail.codeaurora.org/?_task=mail&_action=compose&_id=676833541590a775943df6#
1) Currently gic_write_grpen1(0) is getting called from 
gic_cpu_pm_notifier() for CPU_PM_ENTER in single security state only.
But enabling of group1 non-secure interrupts are done in CPU_PM_EXIT 
path unconditionally. Why are we not disabling group1 non-secure 
interrupts unconditionally in CPU_PM_ENTER(and disabling only in single 
security state)?

2) Why group1 non-secure interrupts are not disabled in kernel during 
cpu hotplug path? Spurious interrupt can still come if we dont disable 
group1 non-secure interrupts, right?

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora 
Forum,
Linux Foundation Collaborative Project