[LU-16362] landing async readhead caused a "uncovered page" panic during sanityN runs

• Type: Bug
• Resolution: Unresolved
• Priority: Critical
• Severity: 3
• Assignee: Alexey Lyashkov
• Reporter: Alexey Lyashkov

Description

Async readhead have skip a "locking" phase

c2791674260 (Wang Shilong 2019-01-21 20:23:47 +0800 658) io->ci_state = CIS_LOCKED;

But separate cl io created, this caused pages sends outside of original page lock and parallel blocking AST caused an "uncovered page" panic hit.

Issue Links

• is related to: LU-16401 various crashes with cl_page_discard vs readhead race
• is related to: LU-16332 LBUG with osc_req_attr_set() uncovered page!