The patch titled Subject: kernel/printk/printk.c: revert "printk: enable interrupts before calling console_trylock_for_printk()" has been removed from the -mm tree. Its filename was kernel-printk-printkc-revert-printk-enable-interrupts-before-calling-console_trylock_for_printk.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Subject: kernel/printk/printk.c: revert "printk: enable interrupts before calling console_trylock_for_printk()" Revert 939f04bec1a4 ("printk: enable interrupts before calling console_trylock_for_printk()"). Andreas reported: : None of the post 3.15 kernel boot for me. They all hang at the GRUB : screen telling me it loaded and started the kernel, but the kernel : itself stops before it prints anything (or even replaces the GRUB : background graphics). 939f04bec1a4 is modest latency reduction. Revert it until we understand the reason for these failures. Reported-by: Andreas Bombe <aeb@xxxxxxxxxx> Cc: Jan Kara <jack@xxxxxxx> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/printk/printk.c | 44 +++++++++++++++------------------------ 1 file changed, 18 insertions(+), 26 deletions(-) diff -puN kernel/printk/printk.c~kernel-printk-printkc-revert-printk-enable-interrupts-before-calling-console_trylock_for_printk kernel/printk/printk.c --- a/kernel/printk/printk.c~kernel-printk-printkc-revert-printk-enable-interrupts-before-calling-console_trylock_for_printk +++ a/kernel/printk/printk.c @@ -1416,9 +1416,10 @@ static int have_callable_console(void) /* * Can we actually use the console at this time on this cpu? * - * Console drivers may assume that per-cpu resources have been allocated. So - * unless they're explicitly marked as being able to cope (CON_ANYTIME) don't - * call them until this CPU is officially up. + * Console drivers may assume that per-cpu resources have + * been allocated. So unless they're explicitly marked as + * being able to cope (CON_ANYTIME) don't call them until + * this CPU is officially up. */ static inline int can_use_console(unsigned int cpu) { @@ -1431,10 +1432,8 @@ static inline int can_use_console(unsign * console_lock held, and 'console_locked' set) if it * is successful, false otherwise. */ -static int console_trylock_for_printk(void) +static int console_trylock_for_printk(unsigned int cpu) { - unsigned int cpu = smp_processor_id(); - if (!console_trylock()) return 0; /* @@ -1609,8 +1608,7 @@ asmlinkage int vprintk_emit(int facility */ if (!oops_in_progress && !lockdep_recursing(current)) { recursion_bug = 1; - local_irq_restore(flags); - return 0; + goto out_restore_irqs; } zap_locks(); } @@ -1718,27 +1716,21 @@ asmlinkage int vprintk_emit(int facility logbuf_cpu = UINT_MAX; raw_spin_unlock(&logbuf_lock); - lockdep_on(); - local_irq_restore(flags); /* If called from the scheduler, we can not call up(). */ - if (in_sched) - return printed_len; - - /* - * Disable preemption to avoid being preempted while holding - * console_sem which would prevent anyone from printing to console - */ - preempt_disable(); - /* - * Try to acquire and then immediately release the console semaphore. - * The release will print out buffers and wake up /dev/kmsg and syslog() - * users. - */ - if (console_trylock_for_printk()) - console_unlock(); - preempt_enable(); + if (!in_sched) { + /* + * Try to acquire and then immediately release the console + * semaphore. The release will print out buffers and wake up + * /dev/kmsg and syslog() users. + */ + if (console_trylock_for_printk(this_cpu)) + console_unlock(); + } + lockdep_on(); +out_restore_irqs: + local_irq_restore(flags); return printed_len; } EXPORT_SYMBOL(vprintk_emit); _ Patches currently in -mm which might be from akpm@xxxxxxxxxxxxxxxxxxxx are i-need-old-gcc.patch arch-alpha-kernel-systblss-remove-debug-check.patch maintainers-akpm-maintenance.patch x86-numa-setup_node_data-drop-dead-code-and-rename-function-checkpatch-fixes.patch input-route-kbd-leds-through-the-generic-leds-layer.patch ocfs2-free-inode-when-i_count-becomes-zero-checkpatch-fixes.patch mm.patch slub-use-new-node-functions-checkpatch-fixes.patch slab-use-get_node-and-kmem_cache_node-functions-fix-2.patch slab-use-get_node-and-kmem_cache_node-functions-fix-2-fix.patch slab-change-int-to-size_t-for-representing-allocation-size.patch mm-page_allocc-unexport-alloc_pages_exact_nid.patch dma-cma-support-arbitrary-bitmap-granularity-fix.patch mm-hugetlbfs-fix-rmapping-for-anonymous-hugepages-with-page_pgoff-v3-fix.patch mm-vmallocc-add-a-schedule-point-to-vmalloc-fix.patch include-linux-mmdebugh-add-vm_warn_once.patch mm-catch-memory-commitment-underflow-fix.patch mm-introduce-do_shared_fault-and-drop-do_fault-fix-fix.patch mm-compactionc-isolate_freepages_block-small-tuneup.patch mm-zpool-implement-common-zpool-api-to-zbud-zsmalloc-fix.patch mm-zpool-prevent-zbud-zsmalloc-from-unloading-when-used-checkpatch-fixes.patch do_shared_fault-check-that-mmap_sem-is-held.patch list-fix-order-of-arguments-for-hlist_add_after_rcu-checkpatch-fixes.patch add-lib-globc-fix.patch lib-list_sortc-convert-to-pr_foo.patch lib-list_sortc-convert-to-pr_foo-fix.patch checkpatch-add-test-for-commit-id-formatting-style-in-commit-log.patch binfmt_elfc-use-get_random_int-to-fix-entropy-depleting-fix.patch fs-isofs-logging-clean-up-fix.patch kexec-implementation-of-new-syscall-kexec_file_load-checkpatch-fixes.patch kexec-support-kexec-kdump-on-efi-systems-fix.patch panic-add-taint_softlockup-fix.patch linux-next.patch drivers-gpio-gpio-zevioc-fix-build.patch drivers-staging-emxx_udc-emxx_udcc-replace-strict_strto-with-kstrto.patch kernel-posix-timersc-code-clean-up-checkpatch-fixes.patch mm-replace-remap_file_pages-syscall-with-emulation-fix.patch memcg-deprecate-memoryforce_empty-knob-fix.patch debugging-keep-track-of-page-owners.patch journal_add_journal_head-debug.patch journal_add_journal_head-debug-fix.patch kernel-forkc-export-kernel_thread-to-modules.patch mutex-subsystem-synchro-test-module.patch slab-leaks3-default-y.patch put_bh-debug.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html