Re: zeroes read back more often than appended

[Pat LaVarre <p.lavarre@ieee.org>]

Kindly offline I received the hint to ...


Try again with both CONFIG_SMP and CONFIG_PREEMPT turned off.


I'm delight to report: works for me!!

Specifically, three times in a row, I passed the test:

ddudfwh mkudffs 65535 3072

Next I will again try to start machines running for days looking for
trouble.  Many thanks.

Pat LaVarre

P.S. I believe drearily conventional, totally uninteresting local detail
includes ...

Just to be careful, before changing my .config, I again confirmed
trouble in a .config more like the defconfig:

$
$ uname -msr
Linux 2.6.0-test7 i686
$
$ egrep '_SMP|_PREE' .config
CONFIG_SMP=y
CONFIG_PREEMPT=y
CONFIG_X86_FIND_SMP_CONFIG=y
CONFIG_X86_SMP=y
$
$ ddudfwh mkudffs 65535 3072
Linux 2.6.0-test7 i686
...
00000000  5e 40 5e 40 5e 40 5e 40  5e 40 5e 40 5e 40 5e 40  |^@^@^@^@^@^@^@^@|
*
012f9000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
$

Next I dedicated a kernel build to alternate .config:

 VERSION = 2
 PATCHLEVEL = 6
 SUBLEVEL = 0
-EXTRAVERSION = -test7
+EXTRAVERSION = .7-udf

Via xconfig Option --> Show Name, I found make xconfig --> Processor
type and features --> Preemptible Kernel.

Changing that PREEMPT option from checked to blank patched my .config:

-CONFIG_PREEMPT=y
+# CONFIG_PREEMPT is not set

Changing the SMP option via xconfig produced many non-comment changes,
again as we saw before in these threads:

+CONFIG_BROKEN_ON_SMP=y
+CONFIG_LOG_BUF_SHIFT=14

-CONFIG_HAVE_DEC_LOCK=y
-CONFIG_LOG_BUF_SHIFT=15
-CONFIG_NR_CPUS=8
-CONFIG_X86_SMP=y
-CONFIG_SMP=y
-CONFIG_X86_EXTRA_IRQS=y
-CONFIG_X86_FIND_SMP_CONFIG=y
-CONFIG_X86_HT=y
-CONFIG_X86_IO_APIC=y
-CONFIG_X86_LOCAL_APIC=y
-CONFIG_X86_MCE_P4THERMAL=y
-CONFIG_X86_MPPARSE=y
-CONFIG_X86_SMP=y
-CONFIG_X86_TRAMPOLINE=y