Messages in this thread | ![/](/images/icornerl.gif) | | Date | Wed, 16 Jul 2003 16:29:15 -0600 | From | Erik Andersen <> | Subject | 2.4.22-pre6 race condition during boot hoses up stat("/")? |
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I recently obtained a P4 and have started building the kernel with SMP enabled (for hyper-threading). I have started noticing some sortof wierd race with mounting root with an Intel ICH5 ide controller...
Normally doing a stat("/", &buf) gives me the correct st_rdev for my root device. But every few boots I find that st_rdev is instead set to the st_rdev of the last IDE device under /proc/ide that happens to be using the ide-disk driver..
Busybox has a find_real_root_device_name() function which depends upon stat("/") giving the correct st_rdev, and this bug causes it to do wierd things.
So for example, when booting I see this:
PCI: Enabling device 00:1f.1 (0005 -> 0007) ICH5: chipset revision 2 ICH5: not 100% native mode: will probe irqs later ide0: BM-DMA at 0xfc00-0xfc07, BIOS settings: hda:DMA, hdb:DMA ide1: BM-DMA at 0xfc08-0xfc0f, BIOS settings: hdc:DMA, hdd:DMA hda: IC35L080AVVA07-0, ATA DISK drive hdb: WDC AC32500H, ATA DISK drive
My root_fs is on /dev/hda2.
But when running the debugger I see....
38 if (stat("/", &rootStat) != 0) (gdb) (gdb) p rootStat.st_rdev $1 = 832 (gdb) p (832 >> 8) & 0xff $2 = 3 (gdb) p 832 & 0xff $3 = 64
Which works out to major 3, minor 64, or /dev/hdb!!!
I've attempted to track down where such a problem could occur, but so far I've come up empty.
-Erik
-- Erik B. Andersen http://codepoet-consulting.com/ --This message was written using 73% post-consumer electrons-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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