similar to: isohybrid boot from logical partition

Thomas Schmitt said: > I am wondering about the meaning or reason of "+20" in this assembler line: > > movl (32+20)(%si), %ecx > > Why that extra offset 20 on the byte offset 32 which is specified by > GPT specs (UEFI 2.4, 5.3.3) ? (Do i get the language wrong ?) Well I've been looking at this. It seems gptmbr.S

I wrote: > Also besides the 16/32 confusion in gptmbr.S there's more weirdness > that looks like a bug: > > /* Check to see if we have EBIOS */ ... > int $0x13 > popw %dx /* restore drive */ > movb $0x08, %ah /* get CHS geometry */ > jc 1f ... [More blather _why_ this is buggy.] Today I see that

It is good to see this ----- Forwarded message from syslinux-bot for Martin Str|mberg <ams at ludd.ltu.se> ----- Date: Sat, 25 Mar 2017 05:54:09 -0700 From: syslinux-bot for Martin Str|mberg <ams at ludd.ltu.se> To: Syslinux commits mailing list <syslinux-commits at zytor.com> Cc: ams at ludd.ltu.se Subject: [syslinux:master] mbr/isohdpfx.S: correct pointer for heads/sectors

From: MartinS <ams at ludd.ltu.se> isohdp[fp]v.S which says E or C if EBIOS or CBIOS is used. isohdppv.S also says G or M if a GPT or MBR partition is detected. Signed-off-by: MartinS <ams at ludd.ltu.se> --- Comments? diff --git a/mbr/Makefile b/mbr/Makefile index be2bded..7095396 100644 --- a/mbr/Makefile +++ b/mbr/Makefile @@ -21,7 +21,8 @@ include $(MAKEDIR)/embedded.mk all:

On Sun, Jan 25, 2015 at 06:13:13PM -0200, Raphael S Carvalho wrote: > On Sat, Nov 22, 2014 at 10:39 AM, Martin Str|mberg <ams at ludd.ltu.se> wrote: > > Hello. > > > > Use the z size specifier to printf-ing size_t variables to get rid of gcc > > warning > > format ?%08x? expects type ?unsigned int?, but argument 2 has type ?long unsigned int? > Please, add

Hi, for some reason David always omits the Cc: to this list. He has now reported to Martin and me the outcome of the latest two MBR test proposals. - His BIOS announces no LBA addressing but another extra feature. This lead to unexpected success in one of David's tests. - The newest fix proposal by Martin is a full success ! Distros which produce isohybrid should consider to already

> On Fri, Feb 6, 2015 at 6:55 AM, Martin Str|mberg <ams at ludd.ltu.se> wrote: > > On Sun, Jan 25, 2015 at 06:13:13PM -0200, Raphael S Carvalho wrote: > >> On Sat, Nov 22, 2014 at 10:39 AM, Martin Str|mberg <ams at ludd.ltu.se> wrote: > >> > Hello. > >> > > >> > Use the z size specifier to printf-ing size_t variables to get rid of

Hi, FYI syslinux upstream has a bugfix. Both in the 6.xx branch and the 4.xx branch. ----- Forwarded message from syslinux-bot for Martin Str|mberg <ams at ludd.ltu.se> ----- Date: Sat, 15 Apr 2017 10:27:08 -0700 From: syslinux-bot for Martin Str|mberg <ams at ludd.ltu.se> To: Syslinux commits mailing list <syslinux-commits at zytor.com> Cc: ams at ludd.ltu.se Subject:

On Fri, Feb 6, 2015 at 6:55 AM, Martin Str|mberg <ams at ludd.ltu.se> wrote: > On Sun, Jan 25, 2015 at 06:13:13PM -0200, Raphael S Carvalho wrote: >> On Sat, Nov 22, 2014 at 10:39 AM, Martin Str|mberg <ams at ludd.ltu.se> wrote: >> > Hello. >> > >> > Use the z size specifier to printf-ing size_t variables to get rid of gcc >> > warning

Hi, Geert Stappers wrote: > Contact David off-list, he did unsubscribe. Can you tell when he unsubscribed (i.e. which of the messages he got as last one) ? > Martin posted elsewhere in this thread "Thomas, you found the bug" > and provided a patch. Open question is whether the fix helps with David's BIOS. The newest answer from Martin indicates that a failure to read

X-Original-In-Reply-To: <CAD0Rxe=5uLCWQ+jfj1J6zepDzqx0vAiBREiwiKOih59MKgBDHg at mail.gmail.com> X-Previous: http://www.syslinux.org/archives/2015-January/023070.html On Mon, Jan 05, 2015 at 08:59:57PM -0500, Gene Cumm wrote: > On Sat, Jan 3, 2015 at 1:21 PM, Geert Stappers wrote: > > On Thu, Jan 01, 2015 at 09:48:16AM -0500, Gene Cumm wrote: > > >> I'm planning on

On Sat, Mar 25, 2017 at 06:51:50PM +0100, Geert Stappers via Syslinux wrote: > It is good to see this > ----- Forwarded message from syslinux-bot for Martin Str|mberg <ams at ludd.ltu.se> ----- > Date: Sat, 25 Mar 2017 05:54:09 -0700 > From: syslinux-bot for Martin Str|mberg <ams at ludd.ltu.se> > Subject: [syslinux:master] mbr/isohdpfx.S: correct pointer for

I've attempted to understand what the isohybrid tool is doing, specifically with the "--partok" flag. As far as I can see, this essentially trims off the first 3 bytes of the custom isohybrid MBR image before applying it to the ISO. Can anyone explain how this enables the ISO to "be happy" on a partition, rather than whole disk? And does anyone have suggestions for what

Hi, Duncan Elliot wrote: > Taking the point that "Syslinux is partition-table-format agnostic" I don't agree with hpa here. SYSLINUX expects MBR partition table entries with absolute addresses. Those are exactly the primary partition entries. That's not what i would call agnostic. But i agree with his assessment that it is very cumbersome to find the own partition start if

Thanks for the clarification Thomas. Thomas Schmitt wrote: > (Did you already tell which partitions exist and in which one do you want > to put your ISO ?) I've tried a number of different structures, but the results are consistent (boots fine from primary partitions, not from logical partitions). For example for a disk partitioned like below: Disk /dev/sdc: 3.8 GiB, 4007657472

Hi, do we have bystanders who can read x86 assembler code or know easy-to-grasp reference docs? (I left machine code programming when i gave up using my VIC-20.) The MBR template isohdppx.bin stems from http://git.zytor.com/syslinux/syslinux.git/tree/mbr/isohdpfx.S with macro PARTITION_SUPPORT defined. One can see the error message text in there: bad_signature: call error .ascii

Hi, the description of wikipedia matches the behavior of fdisk. Statements by hpa several years ago indicate that the relative start LBA of logical partitions is indeed a troublemaker between GRUB and SYSLINUX. --------------------------------------------------------------------- I created by help of fdisk this layout Device Boot Start End Sectors Size Id Type ebr_fdisk.img1

Hi, I have been attempting to set up a multi-boot USB stick (i.e. multiple bootable ISO images on the one stick) I have had good success by: - processing ISO with isohybrid (with "partok" flag) - dd'ing ISO to primary partitions on the USB stick (e.g /dev/sdc2, /dev/sdc3, /dev/sdc4) - installing grub to USB stick and configuring to chainload to these partitions To remove the limit

Hi, Duncan Elliot wrote: > What is the thought process of clearing the ISO MBR? It is not necessary in the partok case, because the partition to which you copy the image encloses the ISO, exposes it for mounting, and protects it from partition editors. (Another idea from assembler riddling turned out to be a red herring.) Without understanding the language or the BIOS habits of MBR

I wrote: > But isohdpfx.S is buggy: ... > /* Check to see if we have EBIOS */ > pushw %dx /* drive number */ > movb $0x41, %ah /* %al == 0 already */ > > Here it claims that al is zero. This is not true. Especially if you Looking at it some more, I've concluded that the bug is the comment. AL doesn't have to be zero and there's no guarantee it