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HomeDefectsLIN6-4439

Not to be fixed

LIN6-4439 : An issue of jffs2 on p2041hfp

Created: Aug 21, 2013 Updated: Apr 19, 2018

Resolved Date: Apr 17, 2018

Previous ID: LIN4-6521

Found In Version: 6.0

Severity: Critical

Applicable for: Wind River Linux 6

Component/s: BSP

Description

do_generic_file_read()  first acquires the page lock, then f->sem,causes an AB-BA deadlock with jffs2_write_begin(), which first
acquires f->sem, then the page lock:
 
jffs2_write_begin
mutex_lock(&f->sem)                         (A)
grab_cache_page_write_begin
    find_lock_page
        lock_page(page)                     (B)
 
 
do_generic_file_read
lock_page_killable(page)                    (B)
    jffs2_readpage
    mutex_lock(&f->sem)                     (A)

Steps to Reproduce

WIND00391781 
0190-jffs2-fix-several-deadlock-issues.patch