Re: Regression in 5.1.0-rc2: PowerBook G4 Aluminum fails to boot - bisected to commit 0df977eafc792
On 3/25/19 3:46 AM, Christophe Leroy wrote: Le 25/03/2019 à 01:49, Larry Finger a écrit : A build of kernel 5.1.0-rc2 resulted in a failure to boot on my PowerBook G4 Aluminum. The bootstrap loads the initial kernel and issues the appropriate start, but the machine hangs at that point. The problem does not depend on the choice of PPC32 processor type. This machine has a 7447A according to /proc/cpuinfo. The problem was bisected to the following: commit 0df977eafc792a5365a7f81d8d5920132e03afad Author: Christophe Leroy Date: Thu Feb 21 10:37:54 2019 + powerpc/6xx: Don't use SPRN_SPRG2 for storing stack pointer while in RTAS When calling RTAS, the stack pointer is stored in SPRN_SPRG2 in order to be able to restore it in case of machine check in RTAS. As machine check is not a perfomance critical path, this patch frees SPRN_SPRG2 by using a field in thread struct instead. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman I reverted this patch and found that the system began execution, and then failed, likely due to the reassignment of SPRN_SPRG2. I had found this problem with 5.1.0-rc1, but -rc2 was out by the time I finished the bisection. Unfortunately, none of the changes in -rc2 fixed the problem. I think I identified the issue, see https://patchwork.ozlabs.org/patch/1063962/ It is now booting properly under QEMU with your .config Could you please test it on your target ? Thanks. That patch fixes the issue. Larry
Re: Regression in 5.1.0-rc2: PowerBook G4 Aluminum fails to boot - bisected to commit 0df977eafc792
On 3/25/19 1:53 AM, Christophe Leroy wrote: Le 25/03/2019 à 01:49, Larry Finger a écrit : A build of kernel 5.1.0-rc2 resulted in a failure to boot on my PowerBook G4 Aluminum. The bootstrap loads the initial kernel and issues the appropriate start, but the machine hangs at that point. Can you please be more explicit ? What do you mean by "issues the appropriate start" ? What is "that point" ? Any messages on the console ? Sorry to be unclear. The bootstrap code prints a line saying "Booting Linux via __start() @ 0x00c0" and then hangs. Your idea of confusion between physical and virtual address sounds right. I am building a kernel with that patch applied now. As it seems to be going quickly, I should have the answer fairly quickly. Thanks, Larry
Re: Regression in 5.1.0-rc2: PowerBook G4 Aluminum fails to boot - bisected to commit 0df977eafc792
Le 25/03/2019 à 01:49, Larry Finger a écrit : A build of kernel 5.1.0-rc2 resulted in a failure to boot on my PowerBook G4 Aluminum. The bootstrap loads the initial kernel and issues the appropriate start, but the machine hangs at that point. The problem does not depend on the choice of PPC32 processor type. This machine has a 7447A according to /proc/cpuinfo. The problem was bisected to the following: commit 0df977eafc792a5365a7f81d8d5920132e03afad Author: Christophe Leroy Date: Thu Feb 21 10:37:54 2019 + powerpc/6xx: Don't use SPRN_SPRG2 for storing stack pointer while in RTAS When calling RTAS, the stack pointer is stored in SPRN_SPRG2 in order to be able to restore it in case of machine check in RTAS. As machine check is not a perfomance critical path, this patch frees SPRN_SPRG2 by using a field in thread struct instead. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman I reverted this patch and found that the system began execution, and then failed, likely due to the reassignment of SPRN_SPRG2. I had found this problem with 5.1.0-rc1, but -rc2 was out by the time I finished the bisection. Unfortunately, none of the changes in -rc2 fixed the problem. I think I identified the issue, see https://patchwork.ozlabs.org/patch/1063962/ It is now booting properly under QEMU with your .config Could you please test it on your target ? Thanks Christophe Attached is the .config that I used. Thanks, Larry
Re: Regression in 5.1.0-rc2: PowerBook G4 Aluminum fails to boot - bisected to commit 0df977eafc792
Le 25/03/2019 à 01:49, Larry Finger a écrit : A build of kernel 5.1.0-rc2 resulted in a failure to boot on my PowerBook G4 Aluminum. The bootstrap loads the initial kernel and issues the appropriate start, but the machine hangs at that point. Can you please be more explicit ? What do you mean by "issues the appropriate start" ? What is "that point" ? Any messages on the console ? Thanks Christophe The problem does not depend on the choice of PPC32 processor type. This machine has a 7447A according to /proc/cpuinfo. The problem was bisected to the following: commit 0df977eafc792a5365a7f81d8d5920132e03afad Author: Christophe Leroy Date: Thu Feb 21 10:37:54 2019 + powerpc/6xx: Don't use SPRN_SPRG2 for storing stack pointer while in RTAS When calling RTAS, the stack pointer is stored in SPRN_SPRG2 in order to be able to restore it in case of machine check in RTAS. As machine check is not a perfomance critical path, this patch frees SPRN_SPRG2 by using a field in thread struct instead. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman I reverted this patch and found that the system began execution, and then failed, likely due to the reassignment of SPRN_SPRG2. I had found this problem with 5.1.0-rc1, but -rc2 was out by the time I finished the bisection. Unfortunately, none of the changes in -rc2 fixed the problem. Attached is the .config that I used. Thanks, Larry
Regression in 5.1.0-rc2: PowerBook G4 Aluminum fails to boot - bisected to commit 0df977eafc792
A build of kernel 5.1.0-rc2 resulted in a failure to boot on my PowerBook G4 Aluminum. The bootstrap loads the initial kernel and issues the appropriate start, but the machine hangs at that point. The problem does not depend on the choice of PPC32 processor type. This machine has a 7447A according to /proc/cpuinfo. The problem was bisected to the following: commit 0df977eafc792a5365a7f81d8d5920132e03afad Author: Christophe Leroy Date: Thu Feb 21 10:37:54 2019 + powerpc/6xx: Don't use SPRN_SPRG2 for storing stack pointer while in RTAS When calling RTAS, the stack pointer is stored in SPRN_SPRG2 in order to be able to restore it in case of machine check in RTAS. As machine check is not a perfomance critical path, this patch frees SPRN_SPRG2 by using a field in thread struct instead. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman I reverted this patch and found that the system began execution, and then failed, likely due to the reassignment of SPRN_SPRG2. I had found this problem with 5.1.0-rc1, but -rc2 was out by the time I finished the bisection. Unfortunately, none of the changes in -rc2 fixed the problem. Attached is the .config that I used. Thanks, Larry # # Automatically generated file; DO NOT EDIT. # Linux/powerpc 5.1.0-rc2 Kernel Configuration # # # Compiler: gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3 # CONFIG_CC_IS_GCC=y CONFIG_GCC_VERSION=40603 CONFIG_CLANG_VERSION=0 CONFIG_CC_HAS_ASM_GOTO=y CONFIG_IRQ_WORK=y CONFIG_BUILDTIME_EXTABLE_SORT=y CONFIG_THREAD_INFO_IN_TASK=y # # General setup # CONFIG_BROKEN_ON_SMP=y CONFIG_INIT_ENV_ARG_LIMIT=32 # CONFIG_COMPILE_TEST is not set CONFIG_LOCALVERSION="" CONFIG_LOCALVERSION_AUTO=y CONFIG_BUILD_SALT="" CONFIG_HAVE_KERNEL_GZIP=y CONFIG_HAVE_KERNEL_XZ=y CONFIG_KERNEL_GZIP=y # CONFIG_KERNEL_XZ is not set CONFIG_DEFAULT_HOSTNAME="(none)" CONFIG_SWAP=y CONFIG_SYSVIPC=y CONFIG_SYSVIPC_SYSCTL=y CONFIG_POSIX_MQUEUE=y CONFIG_POSIX_MQUEUE_SYSCTL=y CONFIG_CROSS_MEMORY_ATTACH=y CONFIG_USELIB=y CONFIG_AUDIT=y CONFIG_HAVE_ARCH_AUDITSYSCALL=y CONFIG_AUDITSYSCALL=y # # IRQ subsystem # CONFIG_GENERIC_IRQ_SHOW=y CONFIG_GENERIC_IRQ_SHOW_LEVEL=y CONFIG_IRQ_DOMAIN=y CONFIG_GENERIC_MSI_IRQ=y CONFIG_IRQ_FORCED_THREADING=y CONFIG_SPARSE_IRQ=y # CONFIG_GENERIC_IRQ_DEBUGFS is not set CONFIG_GENERIC_TIME_VSYSCALL=y CONFIG_GENERIC_CLOCKEVENTS=y CONFIG_GENERIC_CMOS_UPDATE=y # # Timers subsystem # CONFIG_TICK_ONESHOT=y CONFIG_NO_HZ_COMMON=y # CONFIG_HZ_PERIODIC is not set CONFIG_NO_HZ_IDLE=y CONFIG_NO_HZ=y CONFIG_HIGH_RES_TIMERS=y # CONFIG_PREEMPT_NONE is not set CONFIG_PREEMPT_VOLUNTARY=y # CONFIG_PREEMPT is not set # # CPU/Task time and stats accounting # CONFIG_TICK_CPU_ACCOUNTING=y # CONFIG_VIRT_CPU_ACCOUNTING_NATIVE is not set # CONFIG_IRQ_TIME_ACCOUNTING is not set CONFIG_BSD_PROCESS_ACCT=y CONFIG_BSD_PROCESS_ACCT_V3=y CONFIG_TASKSTATS=y CONFIG_TASK_DELAY_ACCT=y CONFIG_TASK_XACCT=y CONFIG_TASK_IO_ACCOUNTING=y # CONFIG_PSI is not set # # RCU Subsystem # CONFIG_TINY_RCU=y # CONFIG_RCU_EXPERT is not set CONFIG_SRCU=y CONFIG_TINY_SRCU=y CONFIG_BUILD_BIN2C=y # CONFIG_IKCONFIG is not set CONFIG_LOG_BUF_SHIFT=20 CONFIG_PRINTK_SAFE_LOG_BUF_SHIFT=13 CONFIG_CGROUPS=y # CONFIG_MEMCG is not set CONFIG_BLK_CGROUP=y # CONFIG_DEBUG_BLK_CGROUP is not set CONFIG_CGROUP_SCHED=y CONFIG_FAIR_GROUP_SCHED=y # CONFIG_CFS_BANDWIDTH is not set # CONFIG_RT_GROUP_SCHED is not set # CONFIG_CGROUP_PIDS is not set # CONFIG_CGROUP_RDMA is not set CONFIG_CGROUP_FREEZER=y CONFIG_CGROUP_DEVICE=y CONFIG_CGROUP_CPUACCT=y CONFIG_CGROUP_PERF=y # CONFIG_CGROUP_DEBUG is not set CONFIG_NAMESPACES=y CONFIG_UTS_NS=y CONFIG_IPC_NS=y CONFIG_USER_NS=y CONFIG_PID_NS=y CONFIG_NET_NS=y # CONFIG_CHECKPOINT_RESTORE is not set CONFIG_SCHED_AUTOGROUP=y # CONFIG_SYSFS_DEPRECATED is not set CONFIG_RELAY=y CONFIG_BLK_DEV_INITRD=y CONFIG_INITRAMFS_SOURCE="" CONFIG_RD_GZIP=y CONFIG_RD_BZIP2=y CONFIG_RD_LZMA=y CONFIG_RD_XZ=y CONFIG_RD_LZO=y CONFIG_RD_LZ4=y # CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE is not set CONFIG_CC_OPTIMIZE_FOR_SIZE=y CONFIG_HAVE_LD_DEAD_CODE_DATA_ELIMINATION=y CONFIG_SYSCTL=y CONFIG_ANON_INODES=y CONFIG_SYSCTL_EXCEPTION_TRACE=y CONFIG_HAVE_PCSPKR_PLATFORM=y CONFIG_BPF=y # CONFIG_EXPERT is not set CONFIG_MULTIUSER=y CONFIG_SGETMASK_SYSCALL=y CONFIG_SYSFS_SYSCALL=y CONFIG_FHANDLE=y CONFIG_POSIX_TIMERS=y CONFIG_PRINTK=y CONFIG_PRINTK_NMI=y CONFIG_BUG=y CONFIG_ELF_CORE=y CONFIG_PCSPKR_PLATFORM=y CONFIG_BASE_FULL=y CONFIG_FUTEX=y CONFIG_FUTEX_PI=y CONFIG_EPOLL=y CONFIG_SIGNALFD=y CONFIG_TIMERFD=y CONFIG_EVENTFD=y CONFIG_SHMEM=y CONFIG_AIO=y CONFIG_IO_URING=y CONFIG_ADVISE_SYSCALLS=y CONFIG_MEMBARRIER=y CONFIG_KALLSYMS=y # CONFIG_KALLSYMS_ALL is not set CONFIG_KALLSYMS_BASE_RELATIVE=y # CONFIG_BPF_SYSCALL is not set # CONFIG_USERFAULTFD is not set CONFIG_ARCH_HAS_MEMBARRIER_CALLBACKS=y CONFIG_RSEQ=y # CONFIG_EMBEDDED is not set CONFIG_HAVE_PERF_EVENTS=y # # Kernel Performance Events And Counters # CONFIG_PERF_EVENTS=y CONFIG_VM_EVENT_COUNTERS=y #
