# git rev-parse -q --verify 3c53776e29f81719efcf8f7a6e30cdf753bee94d^{commit} 3c53776e29f81719efcf8f7a6e30cdf753bee94d already have revision, skipping fetch # git checkout -q -f -B kisskb 3c53776e29f81719efcf8f7a6e30cdf753bee94d # git clean -qxdf # < git log -1 # commit 3c53776e29f81719efcf8f7a6e30cdf753bee94d # Author: Linus Torvalds # Date: Mon Jan 8 11:51:04 2018 -0800 # # Mark HI and TASKLET softirq synchronous # # Way back in 4.9, we committed 4cd13c21b207 ("softirq: Let ksoftirqd do # its job"), and ever since we've had small nagging issues with it. For # example, we've had: # # 1ff688209e2e ("watchdog: core: make sure the watchdog_worker is not deferred") # 8d5755b3f77b ("watchdog: softdog: fire watchdog even if softirqs do not get to run") # 217f69743681 ("net: busy-poll: allow preemption in sk_busy_loop()") # # all of which worked around some of the effects of that commit. # # The DVB people have also complained that the commit causes excessive USB # URB latencies, which seems to be due to the USB code using tasklets to # schedule USB traffic. This seems to be an issue mainly when already # living on the edge, but waiting for ksoftirqd to handle it really does # seem to cause excessive latencies. # # Now Hanna Hawa reports that this issue isn't just limited to USB URB and # DVB, but also causes timeout problems for the Marvell SoC team: # # "I'm facing kernel panic issue while running raid 5 on sata disks # connected to Macchiatobin (Marvell community board with Armada-8040 # SoC with 4 ARMv8 cores of CA72) Raid 5 built with Marvell DMA engine # and async_tx mechanism (ASYNC_TX_DMA [=y]); the DMA driver (mv_xor_v2) # uses a tasklet to clean the done descriptors from the queue" # # The latency problem causes a panic: # # mv_xor_v2 f0400000.xor: dma_sync_wait: timeout! # Kernel panic - not syncing: async_tx_quiesce: DMA error waiting for transaction # # We've discussed simply just reverting the original commit entirely, and # also much more involved solutions (with per-softirq threads etc). This # patch is intentionally stupid and fairly limited, because the issue # still remains, and the other solutions either got sidetracked or had # other issues. # # We should probably also consider the timer softirqs to be synchronous # and not be delayed to ksoftirqd (since they were the issue with the # earlier watchdog problems), but that should be done as a separate patch. # This does only the tasklet cases. # # Reported-and-tested-by: Hanna Hawa # Reported-and-tested-by: Josef Griebichler # Reported-by: Mauro Carvalho Chehab # Cc: Alan Stern # Cc: Greg Kroah-Hartman # Cc: Eric Dumazet # Cc: Ingo Molnar # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux-gcc --version # < git log --format=%s --max-count=1 3c53776e29f81719efcf8f7a6e30cdf753bee94d # < make -s -j 48 ARCH=sparc O=/kisskb/build/linus_sparc-allmodconfig_sparc64 CROSS_COMPILE=/opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux- allmodconfig # Added to kconfig CONFIG_64BIT=n # Added to kconfig CONFIG_BUILD_DOCSRC=n # Added to kconfig CONFIG_HAVE_FTRACE_MCOUNT_RECORD=n # Added to kconfig CONFIG_SAMPLES=n # Added to kconfig CONFIG_MODULE_SIG=n # yes \n | make -s -j 48 ARCH=sparc O=/kisskb/build/linus_sparc-allmodconfig_sparc64 CROSS_COMPILE=/opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux- oldconfig yes: standard output: Broken pipe yes: write error # make -s -j 48 ARCH=sparc O=/kisskb/build/linus_sparc-allmodconfig_sparc64 CROSS_COMPILE=/opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux- :1332:2: warning: #warning syscall io_pgetevents not implemented [-Wcpp] :1335:2: warning: #warning syscall rseq not implemented [-Wcpp] In file included from /kisskb/src/arch/sparc/include/asm/cacheflush.h:11:0, from /kisskb/src/drivers/android/binder.c:54: /kisskb/src/arch/sparc/include/asm/cacheflush_32.h:40:37: warning: 'struct page' declared inside parameter list void sparc_flush_page_to_ram(struct page *page); ^ /kisskb/src/arch/sparc/include/asm/cacheflush_32.h:40:37: warning: its scope is only this definition or declaration, which is probably not what you want In file included from /kisskb/src/arch/sparc/include/asm/cacheflush.h:11:0, from /kisskb/src/drivers/android/binder_alloc.c:20: /kisskb/src/arch/sparc/include/asm/cacheflush_32.h:40:37: warning: 'struct page' declared inside parameter list void sparc_flush_page_to_ram(struct page *page); ^ /kisskb/src/arch/sparc/include/asm/cacheflush_32.h:40:37: warning: its scope is only this definition or declaration, which is probably not what you want /kisskb/src/drivers/char/tpm/tpm2-cmd.c: In function 'tpm2_unseal_trusted': /kisskb/src/drivers/char/tpm/tpm2-cmd.c:730:2: warning: 'blob_handle' may be used uninitialized in this function [-Wmaybe-uninitialized] tpm2_flush_context_cmd(chip, blob_handle, TPM_TRANSMIT_UNLOCKED); ^ /kisskb/src/drivers/input/joystick/analog.c:176:2: warning: #warning Precise timer not defined for this architecture. [-Wcpp] #warning Precise timer not defined for this architecture. ^ In file included from /kisskb/src/arch/sparc/include/asm/cmpxchg.h:7:0, from /kisskb/src/arch/sparc/include/asm/atomic_32.h:17, from /kisskb/src/arch/sparc/include/asm/atomic.h:7, from /kisskb/src/include/linux/atomic.h:5, from /kisskb/src/arch/sparc/include/asm/smp_32.h:25, from /kisskb/src/arch/sparc/include/asm/smp.h:7, from /kisskb/src/arch/sparc/include/asm/switch_to_32.h:5, from /kisskb/src/arch/sparc/include/asm/switch_to.h:7, from /kisskb/src/arch/sparc/include/asm/ptrace.h:120, from /kisskb/src/arch/sparc/include/asm/thread_info_32.h:19, from /kisskb/src/arch/sparc/include/asm/thread_info.h:7, from /kisskb/src/include/linux/thread_info.h:38, from /kisskb/src/include/asm-generic/preempt.h:5, from ./arch/sparc/include/generated/asm/preempt.h:1, from /kisskb/src/include/linux/preempt.h:81, from /kisskb/src/include/linux/spinlock.h:51, from /kisskb/src/include/linux/wait.h:9, from /kisskb/src/include/linux/wait_bit.h:8, from /kisskb/src/include/linux/fs.h:6, from /kisskb/src/fs/ocfs2/file.c:27: /kisskb/src/fs/ocfs2/file.c: In function 'ocfs2_file_write_iter': /kisskb/src/arch/sparc/include/asm/cmpxchg_32.h:28:22: warning: value computed is not used [-Wunused-value] #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) ^ /kisskb/src/fs/ocfs2/file.c:2386:3: note: in expansion of macro 'xchg' xchg(&iocb->ki_complete, saved_ki_complete); ^ In file included from /kisskb/src/include/linux/printk.h:7:0, from /kisskb/src/include/linux/kernel.h:14, from /kisskb/src/include/linux/list.h:9, from /kisskb/src/include/linux/rculist.h:10, from /kisskb/src/include/linux/sched/signal.h:5, from /kisskb/src/drivers/net/usb/hso.c:55: /kisskb/src/drivers/net/usb/hso.c: In function 'hso_serial_set_termios': /kisskb/src/include/linux/kern_levels.h:5:18: warning: format '%d' expects argument of type 'int', but argument 4 has type 'tcflag_t {aka long unsigned int}' [-Wformat=] #define KERN_SOH "\001" /* ASCII Start Of Header */ ^ /kisskb/src/include/linux/kern_levels.h:14:19: note: in expansion of macro 'KERN_SOH' #define KERN_INFO KERN_SOH "6" /* informational */ ^ /kisskb/src/include/linux/printk.h:311:9: note: in expansion of macro 'KERN_INFO' printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) ^ /kisskb/src/drivers/net/usb/hso.c:115:3: note: in expansion of macro 'pr_info' pr_info("[%d:%s] " fmt, \ ^ /kisskb/src/drivers/net/usb/hso.c:1404:3: note: in expansion of macro 'hso_dbg' hso_dbg(0x16, "Termios called with: cflags new[%d] - old[%d]\n", ^ /kisskb/src/include/linux/kern_levels.h:5:18: warning: format '%d' expects argument of type 'int', but argument 5 has type 'tcflag_t {aka long unsigned int}' [-Wformat=] #define KERN_SOH "\001" /* ASCII Start Of Header */ ^ /kisskb/src/include/linux/kern_levels.h:14:19: note: in expansion of macro 'KERN_SOH' #define KERN_INFO KERN_SOH "6" /* informational */ ^ /kisskb/src/include/linux/printk.h:311:9: note: in expansion of macro 'KERN_INFO' printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) ^ /kisskb/src/drivers/net/usb/hso.c:115:3: note: in expansion of macro 'pr_info' pr_info("[%d:%s] " fmt, \ ^ /kisskb/src/drivers/net/usb/hso.c:1404:3: note: in expansion of macro 'hso_dbg' hso_dbg(0x16, "Termios called with: cflags new[%d] - old[%d]\n", ^ /kisskb/src/drivers/tty/serial/sunzilog.c:1132:13: warning: 'sunzilog_putchar' defined but not used [-Wunused-function] static void sunzilog_putchar(struct uart_port *port, int ch) ^ In file included from /kisskb/src/arch/sparc/include/asm/cmpxchg.h:7:0, from /kisskb/src/arch/sparc/include/asm/atomic_32.h:17, from /kisskb/src/arch/sparc/include/asm/atomic.h:7, from /kisskb/src/include/linux/atomic.h:5, from /kisskb/src/arch/sparc/include/asm/smp_32.h:25, from /kisskb/src/arch/sparc/include/asm/smp.h:7, from /kisskb/src/arch/sparc/include/asm/switch_to_32.h:5, from /kisskb/src/arch/sparc/include/asm/switch_to.h:7, from /kisskb/src/arch/sparc/include/asm/ptrace.h:120, from /kisskb/src/arch/sparc/include/asm/thread_info_32.h:19, from /kisskb/src/arch/sparc/include/asm/thread_info.h:7, from /kisskb/src/include/linux/thread_info.h:38, from /kisskb/src/include/asm-generic/preempt.h:5, from ./arch/sparc/include/generated/asm/preempt.h:1, from /kisskb/src/include/linux/preempt.h:81, from /kisskb/src/include/linux/spinlock.h:51, from /kisskb/src/include/linux/seqlock.h:36, from /kisskb/src/include/linux/time.h:6, from /kisskb/src/include/linux/stat.h:19, from /kisskb/src/include/linux/module.h:10, from /kisskb/src/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c:12: /kisskb/src/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c: In function 'ixgbevf_xdp_setup': /kisskb/src/arch/sparc/include/asm/cmpxchg_32.h:28:22: warning: value computed is not used [-Wunused-value] #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) ^ /kisskb/src/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c:4448:4: note: in expansion of macro 'xchg' xchg(&adapter->rx_ring[i]->xdp_prog, adapter->xdp_prog); ^ In file included from /kisskb/src/arch/sparc/include/asm/cacheflush.h:11:0, from /kisskb/src/drivers/staging/media/omap4iss/iss_video.c:14: /kisskb/src/arch/sparc/include/asm/cacheflush_32.h:40:37: warning: 'struct page' declared inside parameter list void sparc_flush_page_to_ram(struct page *page); ^ /kisskb/src/arch/sparc/include/asm/cacheflush_32.h:40:37: warning: its scope is only this definition or declaration, which is probably not what you want In file included from /kisskb/src/arch/sparc/include/asm/page.h:10:0, from /kisskb/src/arch/sparc/include/asm/string_32.h:13, from /kisskb/src/arch/sparc/include/asm/string.h:7, from /kisskb/src/include/linux/string.h:20, from /kisskb/src/include/linux/bitmap.h:9, from /kisskb/src/include/linux/cpumask.h:12, from /kisskb/src/arch/sparc/include/asm/smp_32.h:15, from /kisskb/src/arch/sparc/include/asm/smp.h:7, from /kisskb/src/arch/sparc/include/asm/switch_to_32.h:5, from /kisskb/src/arch/sparc/include/asm/switch_to.h:7, from /kisskb/src/arch/sparc/include/asm/ptrace.h:120, from /kisskb/src/arch/sparc/include/asm/thread_info_32.h:19, from /kisskb/src/arch/sparc/include/asm/thread_info.h:7, from /kisskb/src/include/linux/thread_info.h:38, from /kisskb/src/arch/sparc/include/asm/current.h:15, from /kisskb/src/include/linux/mutex.h:14, from /kisskb/src/include/linux/notifier.h:14, from /kisskb/src/include/linux/clk.h:17, from /kisskb/src/drivers/staging/media/omap4iss/iss_video.c:15: /kisskb/src/include/linux/highmem.h: In function 'clear_user_highpage': /kisskb/src/include/linux/highmem.h:137:31: error: passing argument 1 of 'sparc_flush_page_to_ram' from incompatible pointer type [-Werror=incompatible-pointer-types] clear_user_page(addr, vaddr, page); ^ /kisskb/src/arch/sparc/include/asm/page_32.h:24:27: note: in definition of macro 'clear_user_page' sparc_flush_page_to_ram(page); \ ^ In file included from /kisskb/src/arch/sparc/include/asm/cacheflush.h:11:0, from /kisskb/src/drivers/staging/media/omap4iss/iss_video.c:14: /kisskb/src/arch/sparc/include/asm/cacheflush_32.h:40:6: note: expected 'struct page *' but argument is of type 'struct page *' void sparc_flush_page_to_ram(struct page *page); ^ /kisskb/src/include/linux/highmem.h: In function 'zero_user_segments': /kisskb/src/include/linux/highmem.h:209:20: error: passing argument 1 of 'sparc_flush_page_to_ram' from incompatible pointer type [-Werror=incompatible-pointer-types] flush_dcache_page(page); ^ /kisskb/src/arch/sparc/include/asm/cacheflush_32.h:43:59: note: in definition of macro 'flush_dcache_page' #define flush_dcache_page(page) sparc_flush_page_to_ram(page) ^ /kisskb/src/arch/sparc/include/asm/cacheflush_32.h:40:6: note: expected 'struct page *' but argument is of type 'struct page *' void sparc_flush_page_to_ram(struct page *page); ^ In file included from /kisskb/src/arch/sparc/include/asm/page.h:10:0, from /kisskb/src/arch/sparc/include/asm/string_32.h:13, from /kisskb/src/arch/sparc/include/asm/string.h:7, from /kisskb/src/include/linux/string.h:20, from /kisskb/src/include/linux/bitmap.h:9, from /kisskb/src/include/linux/cpumask.h:12, from /kisskb/src/arch/sparc/include/asm/smp_32.h:15, from /kisskb/src/arch/sparc/include/asm/smp.h:7, from /kisskb/src/arch/sparc/include/asm/switch_to_32.h:5, from /kisskb/src/arch/sparc/include/asm/switch_to.h:7, from /kisskb/src/arch/sparc/include/asm/ptrace.h:120, from /kisskb/src/arch/sparc/include/asm/thread_info_32.h:19, from /kisskb/src/arch/sparc/include/asm/thread_info.h:7, from /kisskb/src/include/linux/thread_info.h:38, from /kisskb/src/arch/sparc/include/asm/current.h:15, from /kisskb/src/include/linux/mutex.h:14, from /kisskb/src/include/linux/notifier.h:14, from /kisskb/src/include/linux/clk.h:17, from /kisskb/src/drivers/staging/media/omap4iss/iss_video.c:15: /kisskb/src/include/linux/highmem.h: In function 'copy_user_highpage': /kisskb/src/include/linux/highmem.h:233:36: error: passing argument 1 of 'sparc_flush_page_to_ram' from incompatible pointer type [-Werror=incompatible-pointer-types] copy_user_page(vto, vfrom, vaddr, to); ^ /kisskb/src/arch/sparc/include/asm/page_32.h:28:27: note: in definition of macro 'copy_user_page' sparc_flush_page_to_ram(page); \ ^ In file included from /kisskb/src/arch/sparc/include/asm/cacheflush.h:11:0, from /kisskb/src/drivers/staging/media/omap4iss/iss_video.c:14: /kisskb/src/arch/sparc/include/asm/cacheflush_32.h:40:6: note: expected 'struct page *' but argument is of type 'struct page *' void sparc_flush_page_to_ram(struct page *page); ^ cc1: some warnings being treated as errors /kisskb/src/scripts/Makefile.build:317: recipe for target 'drivers/staging/media/omap4iss/iss_video.o' failed make[5]: *** [drivers/staging/media/omap4iss/iss_video.o] Error 1 /kisskb/src/scripts/Makefile.build:558: recipe for target 'drivers/staging/media/omap4iss' failed make[4]: *** [drivers/staging/media/omap4iss] Error 2 make[4]: *** Waiting for unfinished jobs.... /kisskb/src/scripts/Makefile.build:558: recipe for target 'drivers/staging/media' failed make[3]: *** [drivers/staging/media] Error 2 make[3]: *** Waiting for unfinished jobs.... /kisskb/src/scripts/Makefile.build:558: recipe for target 'drivers/staging' failed make[2]: *** [drivers/staging] Error 2 make[2]: *** Waiting for unfinished jobs.... /kisskb/src/Makefile:1029: recipe for target 'drivers' failed make[1]: *** [drivers] Error 2 Makefile:146: recipe for target 'sub-make' failed make: *** [sub-make] Error 2 Command 'make -s -j 48 ARCH=sparc O=/kisskb/build/linus_sparc-allmodconfig_sparc64 CROSS_COMPILE=/opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux- ' returned non-zero exit status 2 # rm -rf /kisskb/build/linus_sparc-allmodconfig_sparc64 # Build took: 0:08:16.401096