[LU-19076] resend can hit the original request on server

• Type: Bug
• Resolution: Unresolved
• Priority: Minor
• Severity: 3
• Assignee: Qian Yingjin
• Reporter: Alex Zhuravlev

Description

in some environment the following race is possible:

• client sends GETATTR with say 1K reply buffer
• MDS replies back with 2K buffer (LOVEA has just changed)
• client resends GETATTR with an extended buffer
• MDS finds the original request on on export's list and reject the new one
• client has no reply, times out

if the client holds a lock for this request, then the client can get evicted and applications can may hit EIO problem.

Issue Links

• is related to: LU-3338 IOC_MDC_GETFILESTRIPE can abuse vmalloc()
• is related to: LU-5703 Quiesce client mountpoints from the server