Commit-ID: 7b3d61cc73a1abe4c2c7eaf00093b338c8b233b0 Gitweb: http://git.kernel.org/tip/7b3d61cc73a1abe4c2c7eaf00093b338c8b233b0 Author: Ingo Molnar <mingo@xxxxxxxxxx> AuthorDate: Tue, 29 Aug 2017 13:10:35 +0200 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Tue, 29 Aug 2017 13:10:35 +0200 locking/refcounts, x86/asm: Disable CONFIG_ARCH_HAS_REFCOUNT for the time being Mike Galbraith bisected a boot crash back to the following commit: 7a46ec0e2f48 ("locking/refcounts, x86/asm: Implement fast refcount overflow protection") The crash/hang pattern is: > Symptom is a few splats as below, with box finally hanging. Network > comes up, but neither ssh nor console login is possible. > > ------------[ cut here ]------------ > WARNING: CPU: 4 PID: 0 at net/netlink/af_netlink.c:374 netlink_sock_destruct+0x82/0xa0 > ... > __sk_destruct() > rcu_process_callbacks() > __do_softirq() > irq_exit() > smp_apic_timer_interrupt() > apic_timer_interrupt() We are at -rc7 already, and the code has grown some dependencies, so instead of a plain revert disable the config temporarily, in the hope of getting real fixes. Reported-by: Mike Galbraith <efault@xxxxxx> Tested-by: Mike Galbraith <efault@xxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx> Cc: Elena Reshetova <elena.reshetova@xxxxxxxxx> Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/tip-7a46ec0e2f4850407de5e1d19a44edee6efa58ec@xxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/Kconfig | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6e01f58..efd9df5 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -55,7 +55,8 @@ config X86 select ARCH_HAS_KCOV if X86_64 select ARCH_HAS_MMIO_FLUSH select ARCH_HAS_PMEM_API if X86_64 - select ARCH_HAS_REFCOUNT + # Causing hangs/crashes, see the commit that added this change for details. + select ARCH_HAS_REFCOUNT if BROKEN select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 select ARCH_HAS_SET_MEMORY select ARCH_HAS_SG_CHAIN -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html