Attachment 9952 Details for Bug 10934 – gdb session

gdb session

currentMode-zero (text/plain), 5.35 KB, created by Julien Cristau on 2007-05-12 15:12:48 UTC

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Creator: Julien Cristau

Created: 2007-05-12 15:12:48 UTC

Size: 5.35 KB

patch

obsolete

>1. At the time of the crash:
>
>(gdb) print pScrn->currentMode
>$1 = (DisplayModePtr) 0x0
>(gdb) print pScrn->modes
>$2 = (DisplayModePtr) 0x820a3a0
>(gdb) print *pScrn
>$3 = {driverVersion = 33619970, driverName = 0xb7bb15f0 "savage", 
>  pScreen = 0x820ac30, scrnIndex = 0, configured = 1, origIndex = 0, 
>  imageByteOrder = 0, bitmapScanlineUnit = 32, bitmapScanlinePad = 32, 
>  bitmapBitOrder = 0, numFormats = 0, formats = {{depth = 0 '\0', 
>      bitsPerPixel = 0 '\0', scanlinePad = 0 '\0'}, {depth = 0 '\0', 
>      bitsPerPixel = 0 '\0', scanlinePad = 0 '\0'}, {depth = 0 '\0', 
>      bitsPerPixel = 0 '\0', scanlinePad = 0 '\0'}, {depth = 0 '\0', 
>      bitsPerPixel = 0 '\0', scanlinePad = 0 '\0'}, {depth = 0 '\0', 
>      bitsPerPixel = 0 '\0', scanlinePad = 0 '\0'}, {depth = 0 '\0', 
>      bitsPerPixel = 0 '\0', scanlinePad = 0 '\0'}, {depth = 0 '\0', 
>      bitsPerPixel = 0 '\0', scanlinePad = 0 '\0'}, {depth = 0 '\0', 
>      bitsPerPixel = 0 '\0', scanlinePad = 0 '\0'}}, fbFormat = {
>    depth = 16 '\020', bitsPerPixel = 16 '\020', scanlinePad = 32 ' '}, 
>  bitsPerPixel = 16, pixmap24 = Pix24DontCare, depth = 16, 
>  depthFrom = X_CONFIG, bitsPerPixelFrom = X_PROBED, weight = {red = 5, 
>    green = 6, blue = 5}, mask = {red = 63488, green = 2016, blue = 31}, 
>  offset = {red = 11, green = 5, blue = 0}, rgbBits = 6, gamma = {red = 1, 
>    green = 1, blue = 1}, defaultVisual = 4, maxHValue = 16384, 
>  maxVValue = 2048, virtualX = 1024, virtualY = 768, xInc = 8, 
>  virtualFrom = X_PROBED, displayWidth = 1024, frameX0 = 0, frameY0 = 0, 
>  frameX1 = 1023, frameY1 = 767, zoomLocked = 0, modePool = 0x0, 
>  modes = 0x820a3a0, currentMode = 0x0, confScreen = 0x81f8a90, 
>  monitor = 0x81f8ac8, display = 0x81fe7a0, entityList = 0x8207808, 
>  numEntities = 1, widthmm = 0, heightmm = 0, xDpi = 96, yDpi = 96, 
>  name = 0xb7bb1eba "SAVAGE", driverPrivate = 0x8208f80, privates = 0x8206970, 
>  drv = 0x8206948, module = 0x8208270, colorKey = 0, overlayFlags = 0, 
>  chipset = 0xb7bb172e "Twister", ramdac = 0x0, clockchip = 0x0, 
>  progClock = 1, numClocks = 0, clock = {0 <repeats 128 times>}, 
>  videoRam = 16384, biosBase = 0, memPhysBase = 3893362688, fbOffset = 0, 
>  domainIOBase = 0, memClk = 0, textClockFreq = 0, flipPixels = 0, 
>  options = 0x8207dc8, chipID = 0, chipRev = 0, racMemFlags = 0, 
>  racIoFlags = 0, access = 0x8206150, CurrentAccess = 0x81e8778, 
>  resourceType = MEM_IO, busAccess = 0x8207c58, vtSema = 1, pixmapPrivate = {
>    ptr = 0x0, val = 0, uval = 0, fptr = 0}, silkenMouse = 0, 
>  clockRanges = 0x8209830, adjustFlags = 1, reservedInt = {
>    0 <repeats 16 times>}, entityInstanceList = 0x8207d18, reservedPtr = {
>    0x0 <repeats 15 times>}, Probe = 0xb7b98910 <SavageProbe>, 
>  PreInit = 0xb7b991a1 <SavagePreInit>, 
>  ScreenInit = 0xb7b9f70b <SavageScreenInit>, 
>  SwitchMode = 0x80ca730 <CMapSwitchMode>, 
>  AdjustFrame = 0x80d7140 <xf86XVAdjustFrame>, 
>  EnterVT = 0xb7c1fc40 <glxDRIEnterVT>, LeaveVT = 0xb7c1fbe0 <glxDRILeaveVT>, 
>  FreeScreen = 0, ValidMode = 0xb7ba08e5 <SavageValidMode>, 
>  EnableDisableFBAccess = 0x80f85d0 <xf86CursorEnableDisableFBAccess>, 
>  SetDGAMode = 0x80cb940 <CMapSetDGAMode>, 
>  ChangeGamma = 0x80cb4c0 <CMapChangeGamma>, 
>  PointerMoved = 0x80be320 <xf86PointerMoved>, PMEvent = 0, HandleMessage = 0, 
>  DPMSSet = 0xb7ba2f8f <SavageDPMS>, 
>  LoadPalette = 0xb7ba20e5 <SavageLoadPalette>, SetOverscan = 0, 
>  DriverFunc = 0, reservedFuncs = {0 <repeats 11 times>}}
>
>2. If I set a breakpoint and set the currentMode manually
>(gdb) set pScrn->currentMode = pScrn->modes
>before entering SavageDoAdjustFrame, the program runs.
>
>
>3. Here I look at currentMode before starting the program and set
>a watchpoint to find out where it is being changed.
>
>(gdb) print xf86Screens[0]->currentMode
>$5 = (DisplayModePtr) 0x820a3a0
>(gdb) print *xf86Screens[0]->currentMode
>$6 = {prev = 0x820a900, next = 0x820a440, name = 0x8209dc8 "1024x768", 
>  status = MODE_OK, type = 48, Clock = 65000, HDisplay = 1024, 
>  HSyncStart = 1048, HSyncEnd = 1184, HTotal = 1344, HSkew = 0, 
>  VDisplay = 768, VSyncStart = 771, VSyncEnd = 777, VTotal = 806, VScan = 0, 
>  Flags = 10, ClockIndex = -1, SynthClock = 65000, CrtcHDisplay = 1024, 
>  CrtcHBlankStart = 1024, CrtcHSyncStart = 1048, CrtcHSyncEnd = 1184, 
>  CrtcHBlankEnd = 1344, CrtcHTotal = 1344, CrtcHSkew = 0, CrtcVDisplay = 768, 
>  CrtcVBlankStart = 768, CrtcVSyncStart = 771, CrtcVSyncEnd = 777, 
>  CrtcVBlankEnd = 806, CrtcVTotal = 806, CrtcHAdjusted = 0, CrtcVAdjusted = 0, 
>  PrivSize = 0, Private = 0x0, PrivFlags = 21168449, HSync = 48.3630943, 
>  VRefresh = 60.0038414}
>(gdb) watch xf86Screens[0].currentMode
>Hardware watchpoint 2: xf86Screens[0].currentMode
>(gdb) cont
>Continuing.
>[Switching to Thread -1211197760 (LWP 3203)]
>Hardware watchpoint 2: xf86Screens[0].currentMode
>
>Old value = (DisplayModePtr) 0x820a3a0
>New value = (DisplayModePtr) 0x0
>VidModeSwitchMode (scrnIndex=0, mode=0x820a590)
>    at ../../../../hw/xfree86/common/xf86VidMode.c:372
>372     ../../../../hw/xfree86/common/xf86VidMode.c: No such file or directory.
>        in ../../../../hw/xfree86/common/xf86VidMode.c
>
>>>From xf86VidMode:
> 370     /* Force a mode switch */
> 371     pScrn->currentMode = NULL;
> 372     retval = xf86SwitchMode(pScrn->pScreen, mode);
> 373     /* we failed: restore it */
> 374     if (retval == FALSE)
>
>Obviously it sets currentMode to NULL intentionally. The problem is that currentMode will be used by SavageDoAdjustFrame inside the xf86SwitchMode call.
>

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Attachments on bug 10934: 9950 | 9951 | 9952 | 9953

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