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#debugging
2 posts
Systems debugging
6 min
A Dovecot optimization the compiler had been deleting all along
An IMAP THREAD command was panicking inside Dovecot's array code. The crash was real, but the comment above it described an optimization that hadn't run in any -O2 build ever shipped. ATTR_PURE turned it into dead code, and the same annotation decided which line showed up in the backtrace.
#dovecot#c#imap#debugging
Systems debugging
6 min
The game that rebooted the hypervisor
A friend's gaming VM hard-reset its Proxmox host the instant a game launched, with nothing in the logs. The cause sat below every layer we kept editing. A power transient at game launch tripped a PCIe fault and reset the box.
#proxmox#vfio#gpu#linux