From: Sean Christopherson <seanjc@google.com>
To: Leesoo Ahn <lsahn@ooseel.net>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
"open list:KERNEL VIRTUAL MACHINE (KVM)" <kvm@vger.kernel.org>,
open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v1] KVM: Use memdup_user instead of kernel stack to allocate kvm_guest_debug
Date: Fri, 20 Feb 2026 09:15:28 -0800 [thread overview]
Message-ID: <aZiWsL9al0LPi0rJ@google.com> (raw)
In-Reply-To: <20260210072530.918038-1-lsahn@ooseel.net>
On Tue, Feb 10, 2026, Leesoo Ahn wrote:
> Switch to using memdup_user to allocate its memory because the size of
> kvm_guest_debug is over 512 bytes on Arm64 and is burdened allocation
> from kernel stack.
520 bytes is a lot, but it's not _that_ much, especially since
kvm_arch_vcpu_ioctl_set_guest_debug() is leaf function (ignoring tracing).
Is there an actual problem on arm64? I.e. does this one particular allocation
lead to stack overflows that otherwise don't happen in KVM?
prev parent reply other threads:[~2026-02-20 17:15 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-10 7:25 [PATCH v1] KVM: Use memdup_user instead of kernel stack to allocate kvm_guest_debug Leesoo Ahn
2026-02-20 8:03 ` Leesoo Ahn
2026-02-20 17:15 ` Sean Christopherson [this message]
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