Hi Tetsuo, Thanks for reporting this. Yes i tried it here with a slightly different .config and i did see the problem. I will try to figure out what is happening over here, but before doing that let me ask if this bug is only in the stable series ? Do we know for which kernel does the "nolapic" option doesn't hit this bug ? Also, I assume its not present in 2.6.29-rc ? Thanks, Alok On Mon, 2009-02-09 at 03:19 -0800, Tetsuo Handa wrote: > Hello. > > > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12409 > > Subject : NULL pointer dereference at get_stats() > > Submitter : Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> > > Date : 2008-12-30 12:53 (21 days old) > > References : http://marc.info/?l=linux-kernel&m=123064167008695&w=4 > > Handled-By : Frederik Deweerdt <frederik.deweerdt@xxxxxxxx> > > I made custom initramfs and tested on native environment and KVM and VMware. > This problem happened only in VMware. > > Alok and Daniel (cc: added), can you reproduce this problem? > > Problem description: > > Compiling 2.6.28.4 using config at http://I-love.SAKURA.ne.jp/tmp/config-2.6.28-bug > and booting with "nolapic" option on x86 machine with 2 CPUs, NULL pointer > dereference happens at get_stats() because for_each_possible_cpu() reaches > CPU 1 while "nolapic" option should prevent for_each_possible_cpu() from > reaching CPU 1. > > Compiling 2.6.28.4 using config at http://I-love.SAKURA.ne.jp/tmp/config-2.6.28-nobug > (all options in "Power management and ACPI options" section disabled) > solves this problem. > > Also, this problem seems to be VMware specific. > I couldn't reproduce this problem on native environment and KVM. > > Native environment (no problem): > > CentOS 5.2 (x86_64) and Ubuntu 8.04 (i386) on ThinkPad X60 > > KVM environment (no problem): > > kvm -kernel /boot/vmlinuz-2.6.28.4 -initrd /boot/init -net none -hda /var/tmp/image.img -vnc xx.xx.xx.xx:0 --append "ro nolapic" -smp 2 > on Ubuntu 8.04 (i386) on ThinkPad X60 > > VMware environment (problematic): > > Debian Sarge (i386) / CentOS 5.2 (i386) on VMware workstation 6.5.1 (x86_64) > on CentOS 5.2 (x86_64) on ThinkPad X60 > > Problematic kernel versions: > > 2.6.27.x and 2.6.28.x . > > Regards. > > ----- Custom initramfs ----- > /* > gcc -Wall -O3 -static -o init init.c > echo init | cpio -o -H newc | gzip -9 > /boot/init > */ > #include <sys/mount.h> > #include <sys/types.h> > #include <sys/stat.h> > #include <fcntl.h> > #include <unistd.h> > #include <stdio.h> > #include <string.h> > > int main(int argc, char *argv[]) { > FILE *fp; > char buffer[1024]; > memset(buffer, 0, sizeof(buffer)); > mkdir("/proc", 0755); > mount("none", "/proc", "proc", 0, NULL); > fp = fopen("/proc/cpuinfo", "r"); > while (fgets(buffer, sizeof(buffer) - 1, fp)) > if (strstr(buffer, "processor")) > printf("%s", buffer); > fclose(fp); > fp = fopen("/proc/cmdline", "r"); > fgets(buffer, sizeof(buffer) - 1, fp); > fclose(fp); > printf("%s", buffer); > fflush(stdout); > if (mkdir("/sys", 0755) || mount("/sys/", "/sys/", "sysfs", 0, NULL)) { > printf("mount failed\n"); > while (1) > sleep(1); > } > fp = fopen("/sys/class/net/lo/statistics/rx_packets", "r"); > if (!fp) { > printf("open failed\n"); > while (1) > sleep(1); > } > while (fgets(buffer, sizeof(buffer) - 1, fp)) > ; > fclose(fp); > printf("done\n"); > while (1) > sleep(1); > return 0; > } -- To unsubscribe from this list: send the line "unsubscribe kernel-testers" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
