Bug 21916

Summary: Re: Machine dies sig 12 in ahc driver (Freebsd4.1.1)
Product: Base System Reporter: Justin T. Gibbs <gibbs>
Component: kernAssignee: freebsd-bugs (Nobody) <bugs>
Status: Closed FIXED    
Severity: Affects Only Me CC: FreeBSD-gnats-submit
Priority: Normal    
Version: 1.0-RELEASE   
Hardware: Any   
OS: Any   

Description Justin T. Gibbs 2000-10-11 19:30:01 UTC 
 >	Rsyncing a remote machine's data onto this machine's
 >	vinum drive causes the machine to bus error.
 >
 >	This is repeatable, and occurs on two exactly similar machines.
 >
 >
 >Fatal trace 12: page fault while in kernel mode
 >fault virtual address = 0xbfc00000
 >fault code = supervisor read, page not present
 >intruction pointer = 0x8:0xc0210222
 >stack pointer = 0x10:0xc025e55c
 >frame pointer = 0x10:0xc025e708
 >code segment = base rx0, limit 0xfffff, type 0x1b
 >        = DPL 0, pres 1, def32 1, gran 1
 >processor eflags = interrupt enabled, resume, IOPL = 0
 >current process = Idle
 >interrupt mask =
 >kernel: type 12 trap, code=0
 >
 >stopped at: bus_dmamap_load+0x1ca: movl PTmap(,%eax,4),%edx
 >
 >db>trace
 >bus_dmamap_load(c1e5cdc0,c0290700,0,0,c013af88,c1e5e9cc,0) at bus_dmamap_load+
 				   ^<==== Buffer Pointer
 
 Vinum is passing a buffer with a NULL b_data pointer to the DA driver.
 The first time the CAM stack will reference this pointer just happens
 to be in the ahc driver's call to bus_dmamap_load().
 
 --
 Justin
Comment 1 Jeroen Ruigrok van der Werven freebsd_committer freebsd_triage 2000-10-31 13:32:20 UTC 
State Changed
From-To: open->closed

Followup to existing PR.
Comment 2 Jeroen Ruigrok van der Werven freebsd_committer freebsd_triage 2000-10-31 13:32:20 UTC 
Responsible Changed
From-To: gnats-admin->freebsd-bugs

Refile.