diff options
| author | hpa <hpa> | 2005-08-19 04:24:41 +0000 |
|---|---|---|
| committer | hpa <hpa> | 2005-08-19 04:24:41 +0000 |
| commit | 150bdc95a1efa103c42b9d1f023b896d11d4dfa6 (patch) | |
| tree | 508e8efb0ec9081fb32380944bd79beae47e0fca | |
| parent | 822cb2008b30d3eb283e6299b66a8c024477fbdc (diff) | |
| download | syslinux-150bdc95a1efa103c42b9d1f023b896d11d4dfa6.tar.gz | |
Fix stack-switching mode (USE_PXE_PROVIDED_STACK == 0)
| -rw-r--r-- | pxelinux.asm | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/pxelinux.asm b/pxelinux.asm index a83afd0a..0af25a34 100644 --- a/pxelinux.asm +++ b/pxelinux.asm @@ -198,7 +198,8 @@ ConfigName resb 256-4 ; Configuration file from DHCP option PathPrefix resb 256 ; Path prefix derived from boot file DotQuadBuf resb 16 ; Buffer for dotted-quad IP address IPOption resb 80 ; ip= option buffer -InitStack resd 1 ; Pointer to reset stack +InitStack resd 1 ; Pointer to reset stack (SS:SP) +PXEStack resd 1 ; Saved stack during PXE call ; Warning here: RBFG build 22 randomly overwrites memory location ; [0x5680,0x576c), possibly more. It seems that it gets confused and @@ -1549,11 +1550,21 @@ unmangle_name: ; ; This is the main PXENV+/!PXE entry point, using the PXENV+ ; calling convention. This is a separate local routine so -; we can hook special things from it if necessary. +; we can hook special things from it if necessary. In particular, +; some PXE stacks seem to not like being invoked from anything but +; the initial stack, so humour it. ; pxenv: +%if USE_PXE_PROVIDED_STACK == 0 + mov [cs:PXEStack],sp + mov [cs:PXEStack+2],ss + lss sp,[cs:InitStack] +%endif .jump: call 0:pxe_thunk ; Default to calling the thunk +%if USE_PXE_PROVIDED_STACK == 0 + lss sp,[cs:PXEStack] +%endif cld ; Make sure DF <- 0 ret @@ -2512,7 +2523,8 @@ pxe_udp_read_pkt: ; Misc initialized (data) variables ; alignb 4, db 0 -BaseStack dd StackBuf ; SS:ESP of base stack +BaseStack dd StackBuf ; ESP of base stack + dw 0 ; SS of base stack NextSocket dw 49152 ; Counter for allocating socket numbers KeepPXE db 0 ; Should PXE be kept around? |