Since nobody seems tempted to reply ;-), I'll add a bit more info myself...
On 3 Jul, this message from To: [EMAIL PROTECTED] echoed through cyberspace: > I've come across a probelm with X 4.1 and 4.2 (4.0 was fine). I'm trying > to avoid using shadowfb for performance reasons. > > Anyway, upon initialization, I get a segfault whn not using shadowfb. > Here's the backtrace: > > Program received signal SIGSEGV, Segmentation fault. > 0x10253c9c in fbBlt (srcLine=0x10af2f68, srcStride=4, srcX=0, > dstLine=0x30545010, dstStride=1536, dstX=0, width=128, height=0, alu=3, > pm=4294967295, bpp=32, reverse=0, upsidedown=0) at fbblt.c:174 [snip] > > dstLine in fbBlt() points to nowhere. More hard looking revealed that the framebuffer line length is calculated wrong (too big), making the framebuffer access go horribly out of bounds. In drivers/fbdev/fbdev.c, FBDevPreInit(), line 528: pScrn->displayWidth = fbdevHWGetLineLength(pScrn)/(fbdevHWGetDepth(pScrn,NULL) >> 3); fbdevHWGetLineLength() is OK; but fbdevHWGetDepth() returns 24. This is running depth 24, but the framebuffer is 32 bpp. So, to get the line length in pixels, the calculation should be done with fbbpp instead of depth. Now, the question is: how? fbdevHWGetDepth() has a second argument, an int *. If provided, it is filled with the fbbpp as: fPtr->var.bits_per_pixel. Wouldn't this be the better choice for calculating the line length? I'll test this as soon as the recompile finishes... Comments? Cheers Michel ------------------------------------------------------------------------- Michel Lanners | " Read Philosophy. Study Art. 23, Rue Paul Henkes | Ask Questions. Make Mistakes. L-1710 Luxembourg | email [EMAIL PROTECTED] | http://www.cpu.lu/~mlan | Learn Always. " _______________________________________________ Xpert mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/xpert
