Hi all, I am new to Syslinux and Memdisk. I setup a PXE boot server that services an image file via memdisk. This works very well. However, I am trying to figure out as to where memdisk the image puts in memory? On the wiki page it says: "MEMDISK simulates a disk by claiming a chunk of high memory for the disk and a (very small - 2K typical) chunk of low (DOS) memory for the driver itself, then hooking the INT 13h (disk driver) and INT 15h (memory query) BIOS interrupts." Well, where is that "high memory chunk"? Thanks! --Martin
On Tue, May 14, 2013 at 12:04 PM, Martin Osterloh <Martin.Osterloh at dartmouth.edu> wrote:> Hi all, > > I am new to Syslinux and Memdisk. I setup a PXE boot server that services an image file via memdisk. This works very well.> Well, where is that "high memory chunk"?Tried utils/memdiskfind or dosutil/mdiskchk.com? It'll also be listed in the e820 memory map (although likely unreliable). -- -Gene
What I am trying to do is booting my OS (incl. custom bootloader) via MEMDISK and have the harddisk image in memory (a diskless system so to say). I found a way to identify the MEMDISK image in memory. I set the size of the harddisk image to my liking. While going through my memory map, I just look for an unusable chunk of that exact size. Chances are pretty low that there is a 2nd chunk of memory with exactly the same (odd) size. Probably not the perfect way but it works for me. -----Original Message----- From: syslinux-bounces at zytor.com [mailto:syslinux-bounces at zytor.com] On Behalf Of Jeffrey Hutzelman Sent: Wednesday, May 15, 2013 2:31 PM To: For discussion of Syslinux and tftp-hpa Cc: jhutz at cmu.edu Subject: Re: [syslinux] MEMDISK location in memory On Wed, 2013-05-15 at 15:10 +0000, Martin Osterloh wrote:> Thanks for your reply. I would really like to use the memory map since > this is most convenient for me. I noticed that there is an additional > entry in the memory map. However, I am trying to find out what type > MEMDISK uses? Any information on this?What are you really trying to do? _______________________________________________ Syslinux mailing list Submissions to Syslinux at zytor.com Unsubscribe or set options at: http://www.zytor.com/mailman/listinfo/syslinux Please do not send private replies to mailing list traffic.
On 05/15/2013 01:31 PM, Martin Osterloh wrote:> > I found a way to identify the MEMDISK image in memory. I set the > size of the harddisk image to my liking. While going through my memory map, I > just look for an unusable chunk of that exact size. Chances are pretty > low that there is a 2nd chunk of memory with exactly the same (odd) size. >This *will* break if the memory area chosen abuts an already reserved memory area. This is not unusual. -hpa