Re: [PATCHv3 0/2]
From: Sean Christopherson <seanjc@google.com>
Date: 2025-02-28 14:32:49
Also in:
kvm, virtualization
On Fri, Feb 28, 2025, Sean Christopherson wrote:
On Fri, Feb 28, 2025, Lei Yang wrote:quoted
Hi Keith V3 introduced a new bug, the following error messages from qemu output after applying this patch to boot up a guest.Doh, my bug. Not yet tested, but this should fix things. Assuming it does, I'll post a v3 so I can add my SoB.
v4 Confirmed that it worked, but deleting the pre-mutex check for ONCE_COMPLETED. Will post v4 later today.
quoted hunk ↗ jump to hunk
diff --git a/include/linux/call_once.h b/include/linux/call_once.h index ddcfd91493ea..b053f4701c94 100644 --- a/include/linux/call_once.h +++ b/include/linux/call_once.h@@ -35,10 +35,12 @@ static inline int call_once(struct once *once, int (*cb)(struct once *)) return 0; guard(mutex)(&once->lock); - WARN_ON(atomic_read(&once->state) == ONCE_RUNNING); - if (atomic_read(&once->state) != ONCE_NOT_STARTED) + if (WARN_ON(atomic_read(&once->state) == ONCE_RUNNING)) return -EINVAL; + if (atomic_read(&once->state) == ONCE_COMPLETED) + return 0; + atomic_set(&once->state, ONCE_RUNNING); r = cb(once); if (r)