>On Sat, Nov 28, 2015 at 07:12:47AM +0000, Xulei (Stone) wrote: >> Hi, >> Recently, i use a script to continuously reset a VM and >> i found my VM frequently halts at "Attempting to allocate >> VGA stack via pmm call". After analyzing, i think it may >> be a problem of SeaBIOS. >> >> From the log(attached below), we can see handle_post() >> executes twice and this makes the destination address of >> "Relocating init" change when the 2nd reset command comes. >> This also influences on the source address of "Copying MPTABLE". >> At last, the VM will be stuck at attempting to allocate VGA >> stack via pmm call. >> >> Could you offer me a solution to fix this problem? >> >> ==============bad SeaBIOS log====== >> SeaBIOS (version rel-1.8.1-0-g4adadbd-20151127_220019-UVP) >> No Xen hypervisor found. >> Running on QEMU (i440fx) >> Running on KVM >> RamSize: 0xc0000000 [cmos] >> Now vcpu cpu_id = 0 <<========= i >> add >> Static seabios entry times =1 <<========= i >> add >> Relocating init from 0x000dbb30 to 0xbffad2c0 (size 76928) >> Found QEMU fw_cfg >> SeaBIOS (version rel-1.8.1-0-g4adadbd-20151127_220019-UVP) <<========= >> handle_post() execute again? > >If seabios resets before it sets HaveRunPost then it probably wont >work well, as it will rerun the POST code without resetting the global >variables it has modified. > >Unfortunately, it's not clear to me that we can simply move the >setting of HaveRunPost to an earlier point, as the handle_resume() >code would need to be audited to ensure it can run even if POST hasn't >completed.
I move HaveRunPost = 1 in the very early point of POST phase (begin at handle_post()), so that when the 2nd reset comes, HaveRunPost is already 1 which makes entry_post jmps to handle_resume() instead of handle_post(). As we know, handle_resume() will reset all global variables. Can you tell me is this solution ok? or, does this have some side effects? >So, it looks like a fix for this will take some further analysis. > >-Kevin _______________________________________________ SeaBIOS mailing list [email protected] http://www.seabios.org/mailman/listinfo/seabios
