[Bug 304636] Re: -hda FAT:. limited to 504MBytes

[Bryce Harrington <304636@bugs.launchpad.net>]

Hi Pedro,

Sorry to hear of your difficulty, but given the age of this bug report,
I'd strongly urge you to file a new bug report.  Since this was last
looked at over 10 years ago, it's extremely likely your issue is
completely unrelated to the originally reported one.

Here are a couple pages on how to write effective bug reports, that I'd
encourage reading to ensure your report is actionable and can
(hopefully) get resolved expediently:

  * https://help.ubuntu.com/community/ReportingBugs
  * https://ubuntu.com/server/docs/reporting-bugs

A few other tips specific to qemu (per the upstream bug tracker):

  * Include the QEMU release version or the git commit hash into the description, so that it is later still clear in which version you have found the bug. Reports against the latest release or even the latest development tree are usually acted upon faster.
  * Include the full command line used to launch the QEMU guest.
  * Reproduce the problem directly with a QEMU command-line. Avoid frontends and management stacks, to ensure that the bug is in QEMU itself and not in a frontend.
  * Include information about the host and guest (operating system, version, 32/64-bit).

-- 
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/304636

Title:
  -hda FAT:. limited to 504MBytes

Status in QEMU:
  Confirmed
Status in qemu package in Ubuntu:
  Won't Fix

Bug description:
  Binary package hint: qemu

  The size of the virtual FAT file system (for sharing a particular directory with Guest OS) is hard-coded to be limited to 504MBytes, in block-vvfat.c
  --
  /* 504MB disk*/
  bs->cyls=1024; bs->heads=16; bs->secs=63;
  --

  If the directory contents exceeds this is stops with an assert
  --
  qemu: block-vvfat.c:97: array_get: Assertion `index < array->next' failed.
  Aborted
  --

  Also the FAT16 mode (default) only uses 8KByte cluster sizes which prevents the above being increased. 16KByte and 32KByte sectors can be selected with the following patch
  --
  --- block-vvfat.c_orig  2008-12-02 12:37:28.000000000 -0700
  +++ block-vvfat.c       2008-12-02 19:50:35.000000000 -0700
  @@ -1042,6 +1042,12 @@
          s->fat_type = 32;
       } else if (strstr(dirname, ":16:")) {
          s->fat_type = 16;
  +    } else if (strstr(dirname, ":16-16K:")) {
  +       s->fat_type = 16;
  +       s->sectors_per_cluster=0x20;
  +    } else if (strstr(dirname, ":16-32K:")) {
  +       s->fat_type = 16;
  +       s->sectors_per_cluster=0x40;
       } else if (strstr(dirname, ":12:")) {
          s->fat_type = 12;
          s->sector_count=2880;
  --

  Cheers,
  Mungewell

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/304636/+subscriptions