Bug 183301
| Summary: | GCC 4.1 and SPCA5XX don't work together | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Panos Prokopiou <pprok> |
| Component: | gcc | Assignee: | Jakub Jelinek <jakub> |
| Status: | CLOSED NOTABUG | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 5 | ||
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2006-03-10 00:44:40 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
That doesn't imply it is a GCC bug, it might very well be a kernel bug, where e.g. its undefined behavior exhibits different observable behavior depending on optimizations GCC is doing. I don't have such a webcam, so unless you debug which exact function gets miscompiled (if any) with which gcc options, there is nothing I can do about it. You should try: 1) if the module consists of several .c source files, try to do say a binary search, compile some files with GCC 4.1, some with GCC 4.0 and load that into GCC 4.1. compiled kernel 2) try different optimization options (-O1, -O2, -Os) 3) when you locate particular .c file, you can do a binary search within it, if say -O1 or -O2 instead of -Os helps, then compile the file with -Os and with -O2 into assembly, then weld first half of the routines from one .s file with second half of the routines with the other file etc. (or with GCC 4.0 vs. GCC 4.1) Alternatively, try to figure out where exactly it hangs and debug why. it just needed -fno-unit-at-a-time. The driver IMHO is a mess. It has even function definitions inside header files. I cannot blame gcc or kernel for this... Anyway, it is NOTABUG, it is AMESS. it just needed -fno-unit-at-a-time. This driver is a total mess IHMO. It even has function definitions inside header files. GCC and kernel not to blame. so NOTABUG, AMESS really. |
Description of problem: I can't get spca5xx module working when compiling with gcc version 4.1.0 20060219 (Red Hat 4.1.0-0.29). The system freezes when the device /dev/video0 is read. I tried to track the problem, located (not fixed) around *_interruptible calls BUT it doesn't seem to be a kernel bug because suse's gcc 4.0 (and a little editing to change 4.0 to 4.1 to make the module load) was enough to make my webcam work. ..or it's binutils fault? Version-Release number of selected component (if applicable): [pprok@localhost spca5xx-20060202]$ rpm -qa | grep kernel kernel-2.6.15-1.1977_FC5 (sources are installed as discribed on release notes) spca5xx-20060202 [pprok@localhost spca5xx-20060202]$ gcc -v Using built-in specs. Target: i386-redhat-linux Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-libgcj-multifile --enable-languages=c,c++,objc,obj-c++,java,fortran,ada --enable-java-awt=gtk --disable-dssi --with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre --with-cpu=generic --host=i386-redhat-linux Thread model: posix gcc version 4.1.0 20060219 (Red Hat 4.1.0-0.29) [pprok@localhost spca5xx-20060202]$ env LD_LIBRARY_PATH=/lib:/mnt/usr/lib /mnt/usr/bin/gcc -v Using built-in specs. Target: i586-suse-linux Configured with: ../configure --enable-threads=posix --prefix=/usr --with-local-prefix=/usr/local --infodir=/usr/share/info --mandir=/usr/share/man --libdir=/usr/lib --libexecdir=/usr/lib --enable-languages=c,c++,objc,f95,java,ada --disable-checking --with-gxx-include-dir=/usr/include/c++/4.0.2 --enable-java-awt=gtk --disable-libjava-multilib --with-slibdir=/lib --with-system-zlib --enable-shared --enable-__cxa_atexit --without-system-libunwind --host=i586-suse-linux Thread model: posix gcc version 4.0.2 20050901 (prerelease) (SUSE Linux) How reproducible: #include <stdio.h> int main(int argc, char ** argv) { FILE* video; char tmp; video = fopen("/dev/video0", "r"); if (!video) { printf("Cannot open /dev/video0\n"); exit(-1); } if (1 != fread(&tmp, 1, 1, video)) // PROBLEM printf("Cannot read /dev/video0\n"); if (EOF == fclose(video)) { printf("Cannot close /dev/video0\n"); exit(-1); } return 0; } Steps to Reproduce: 1. build the module 2. load it 3. try to open /dev/video0, either using cat, or my prog 4. the system dies and needs a cold reboot (usally it just auto reboots instantly) Additional info: Fedora Core 5 Test3 [pprok@localhost spca5xx-20060202]$ make clean ; make V=1 rm -r -f drivers/usb/*.o drivers/usb/.spcadecoder.o.cmd \ drivers/usb/.spca5xx.o.cmd *.o *.ko *.mod.* .[a-z]* core *.i Building SPCA5XX driver for 2.5/2.6 kernel. Remember: you must have read/write access to your kernel source tree. make -C /lib/modules/`uname -r`/build SUBDIRS=/home/pprok/tmp/spca5xx-20060202 CC=cc modules make[1]: Entering directory `/usr/src/linux-2.6.15.i686' mkdir -p /home/pprok/tmp/spca5xx-20060202/.tmp_versions make -f scripts/Makefile.build obj=/home/pprok/tmp/spca5xx-20060202 cc -Wp,-MD,/home/pprok/tmp/spca5xx-20060202/drivers/usb/.spca5xx.o.d -nostdinc -isystem /usr/lib/gcc/i386-redhat-linux/4.1.0/include -D__KERNEL__ -Iinclude -include include/linux/autoconf.h -Iinclude/asm-i386/mach-default -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -ffreestanding -Os -fomit-frame-pointer -g -pipe -msoft-float -fno-builtin-sprintf -fno-builtin-log2 -fno-builtin-puts -mpreferred-stack-boundary=2 -march=i686 -mtune=pentium4 -mregparm=3 -Iinclude/asm-i386/mach-default -Wdeclaration-after-statement -Wno-pointer-sign -DSPCA50X_ENABLE_DEBUG -DSPCA50X_ENABLE_COMPRESSION -DCONFIG_USB_SPCA5XX_MODULE=1 -DMODULE -D__KERNEL__ -DVID_HARDWARE_SPCA5XX=0xFF -DSPCA5XX_VERSION=\"00.57.09\" -DMODULE -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(spca5xx)" -D"KBUILD_MODNAME=KBUILD_STR(spca5xx)" -c -o /home/pprok/tmp/spca5xx-20060202/drivers/usb/.tmp_spca5xx.o /home/pprok/tmp/spca5xx-20060202/drivers/usb/spca5xx.c cc -Wp,-MD,/home/pprok/tmp/spca5xx-20060202/drivers/usb/.spcadecoder.o.d -nostdinc -isystem /usr/lib/gcc/i386-redhat-linux/4.1.0/include -D__KERNEL__ -Iinclude -include include/linux/autoconf.h -Iinclude/asm-i386/mach-default -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -ffreestanding -Os -fomit-frame-pointer -g -pipe -msoft-float -fno-builtin-sprintf -fno-builtin-log2 -fno-builtin-puts -mpreferred-stack-boundary=2 -march=i686 -mtune=pentium4 -mregparm=3 -Iinclude/asm-i386/mach-default -Wdeclaration-after-statement -Wno-pointer-sign -DSPCA50X_ENABLE_DEBUG -DSPCA50X_ENABLE_COMPRESSION -DCONFIG_USB_SPCA5XX_MODULE=1 -DMODULE -D__KERNEL__ -DVID_HARDWARE_SPCA5XX=0xFF -DSPCA5XX_VERSION=\"00.57.09\" -DMODULE -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(spcadecoder)" -D"KBUILD_MODNAME=KBUILD_STR(spca5xx)" -c -o /home/pprok/tmp/spca5xx-20060202/drivers/usb/.tmp_spcadecoder.o /home/pprok/tmp/spca5xx-20060202/drivers/usb/spcadecoder.c /home/pprok/tmp/spca5xx-20060202/drivers/usb/spcadecoder.c: In function âfun_Dâ: /home/pprok/tmp/spca5xx-20060202/drivers/usb/spcadecoder.c:756: warning: value computed is not used ld -m elf_i386 -m elf_i386 -r -o /home/pprok/tmp/spca5xx-20060202/spca5xx.o /home/pprok/tmp/spca5xx-20060202/drivers/usb/spca5xx.o /home/pprok/tmp/spca5xx-20060202/drivers/usb/spcadecoder.o Building modules, stage 2. make -rR -f /usr/src/linux-2.6.15.i686/scripts/Makefile.modpost scripts/mod/modpost -m -a -i /usr/src/linux-2.6.15.i686/Module.symvers /home/pprok/tmp/spca5xx-20060202/spca5xx.o cc -Wp,-MD,/home/pprok/tmp/spca5xx-20060202/.spca5xx.mod.o.d -nostdinc -isystem /usr/lib/gcc/i386-redhat-linux/4.1.0/include -D__KERNEL__ -Iinclude -include include/linux/autoconf.h -Iinclude/asm-i386/mach-default -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -ffreestanding -Os -fomit-frame-pointer -g -pipe -msoft-float -fno-builtin-sprintf -fno-builtin-log2 -fno-builtin-puts -mpreferred-stack-boundary=2 -march=i686 -mtune=pentium4 -mregparm=3 -Iinclude/asm-i386/mach-default -Wdeclaration-after-statement -Wno-pointer-sign -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(spca5xx)" -D"KBUILD_MODNAME=KBUILD_STR(spca5xx)" -DMODULE -c -o /home/pprok/tmp/spca5xx-20060202/spca5xx.mod.o /home/pprok/tmp/spca5xx-20060202/spca5xx.mod.c ld -m elf_i386 -m elf_i386 -r -o /home/pprok/tmp/spca5xx-20060202/spca5xx.ko /home/pprok/tmp/spca5xx-20060202/spca5xx.o /home/pprok/tmp/spca5xx-20060202/spca5xx.mod.o make[1]: Leaving directory `/usr/src/linux-2.6.15.i686' SUSE 10.0 [pprok@localhost spca5xx-20060202]$ make clean; env LD_LIBRARY_PATH=/lib:/mnt/usr/lib make CC=/mnt/usr/bin/gcc V=1 rm -r -f drivers/usb/*.o drivers/usb/.spcadecoder.o.cmd \ drivers/usb/.spca5xx.o.cmd *.o *.ko *.mod.* .[a-z]* core *.i Building SPCA5XX driver for 2.5/2.6 kernel. Remember: you must have read/write access to your kernel source tree. make -C /lib/modules/`uname -r`/build SUBDIRS=/home/pprok/tmp/spca5xx-20060202 CC=/mnt/usr/bin/gcc modules make[1]: Entering directory `/usr/src/linux-2.6.15.i686' mkdir -p /home/pprok/tmp/spca5xx-20060202/.tmp_versions make -f scripts/Makefile.build obj=/home/pprok/tmp/spca5xx-20060202 /mnt/usr/bin/gcc -Wp,-MD,/home/pprok/tmp/spca5xx-20060202/drivers/usb/.spca5xx.o.d -nostdinc -isystem /mnt/usr/bin/../lib/gcc/i586-suse-linux/4.0.2/include -D__KERNEL__ -Iinclude -include include/linux/autoconf.h -Iinclude/asm-i386/mach-default -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -ffreestanding -Os -fomit-frame-pointer -g -pipe -msoft-float -fno-builtin-sprintf -fno-builtin-log2 -fno-builtin-puts -mpreferred-stack-boundary=2 -march=i686 -mtune=pentium4 -mregparm=3 -Iinclude/asm-i386/mach-default -Wdeclaration-after-statement -Wno-pointer-sign -DSPCA50X_ENABLE_DEBUG -DSPCA50X_ENABLE_COMPRESSION -DCONFIG_USB_SPCA5XX_MODULE=1 -DMODULE -D__KERNEL__ -DVID_HARDWARE_SPCA5XX=0xFF -DSPCA5XX_VERSION=\"00.57.09\" -DMODULE -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(spca5xx)" -D"KBUILD_MODNAME=KBUILD_STR(spca5xx)" -c -o /home/pprok/tmp/spca5xx-20060202/drivers/usb/.tmp_spca5xx.o /home/pprok/tmp/spca5xx-20060202/drivers/usb/spca5xx.c /mnt/usr/bin/gcc -Wp,-MD,/home/pprok/tmp/spca5xx-20060202/drivers/usb/.spcadecoder.o.d -nostdinc -isystem /mnt/usr/bin/../lib/gcc/i586-suse-linux/4.0.2/include -D__KERNEL__ -Iinclude -include include/linux/autoconf.h -Iinclude/asm-i386/mach-default -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -ffreestanding -Os -fomit-frame-pointer -g -pipe -msoft-float -fno-builtin-sprintf -fno-builtin-log2 -fno-builtin-puts -mpreferred-stack-boundary=2 -march=i686 -mtune=pentium4 -mregparm=3 -Iinclude/asm-i386/mach-default -Wdeclaration-after-statement -Wno-pointer-sign -DSPCA50X_ENABLE_DEBUG -DSPCA50X_ENABLE_COMPRESSION -DCONFIG_USB_SPCA5XX_MODULE=1 -DMODULE -D__KERNEL__ -DVID_HARDWARE_SPCA5XX=0xFF -DSPCA5XX_VERSION=\"00.57.09\" -DMODULE -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(spcadecoder)" -D"KBUILD_MODNAME=KBUILD_STR(spca5xx)" -c -o /home/pprok/tmp/spca5xx-20060202/drivers/usb/.tmp_spcadecoder.o /home/pprok/tmp/spca5xx-20060202/drivers/usb/spcadecoder.c ld -m elf_i386 -m elf_i386 -r -o /home/pprok/tmp/spca5xx-20060202/spca5xx.o /home/pprok/tmp/spca5xx-20060202/drivers/usb/spca5xx.o /home/pprok/tmp/spca5xx-20060202/drivers/usb/spcadecoder.o Building modules, stage 2. make -rR -f /usr/src/linux-2.6.15.i686/scripts/Makefile.modpost scripts/mod/modpost -m -a -i /usr/src/linux-2.6.15.i686/Module.symvers /home/pprok/tmp/spca5xx-20060202/spca5xx.o /mnt/usr/bin/gcc -Wp,-MD,/home/pprok/tmp/spca5xx-20060202/.spca5xx.mod.o.d -nostdinc -isystem /mnt/usr/bin/../lib/gcc/i586-suse-linux/4.0.2/include -D__KERNEL__ -Iinclude -include include/linux/autoconf.h -Iinclude/asm-i386/mach-default -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -ffreestanding -Os -fomit-frame-pointer -g -pipe -msoft-float -fno-builtin-sprintf -fno-builtin-log2 -fno-builtin-puts -mpreferred-stack-boundary=2 -march=i686 -mtune=pentium4 -mregparm=3 -Iinclude/asm-i386/mach-default -Wdeclaration-after-statement -Wno-pointer-sign -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(spca5xx)" -D"KBUILD_MODNAME=KBUILD_STR(spca5xx)" -DMODULE -c -o /home/pprok/tmp/spca5xx-20060202/spca5xx.mod.o /home/pprok/tmp/spca5xx-20060202/spca5xx.mod.c ld -m elf_i386 -m elf_i386 -r -o /home/pprok/tmp/spca5xx-20060202/spca5xx.ko /home/pprok/tmp/spca5xx-20060202/spca5xx.o /home/pprok/tmp/spca5xx-20060202/spca5xx.mod.o make[1]: Leaving directory `/usr/src/linux-2.6.15.i686'