# git rev-parse -q --verify 2be7d348fe924f0c5583c6a805bd42cecda93104^{commit} 2be7d348fe924f0c5583c6a805bd42cecda93104 already have revision, skipping fetch # git checkout -q -f -B kisskb 2be7d348fe924f0c5583c6a805bd42cecda93104 # git clean -qxdf # < git log -1 # commit 2be7d348fe924f0c5583c6a805bd42cecda93104 # Author: Linus Torvalds # Date: Tue Nov 26 11:34:06 2019 -0800 # # Revert "vfs: properly and reliably lock f_pos in fdget_pos()" # # This reverts commit 0be0ee71816b2b6725e2b4f32ad6726c9d729777. # # I was hoping it would be benign to switch over entirely to FMODE_STREAM, # and we'd have just a couple of small fixups we'd need, but it looks like # we're not quite there yet. # # While it worked fine on both my desktop and laptop, they are fairly # similar in other respects, and run mostly the same loads. Kenneth # Crudup reports that it seems to break both his vmware installation and # the KDE upower service. In both cases apparently leading to timeouts # due to waitinmg for the f_pos lock. # # There are a number of character devices in particular that definitely # want stream-like behavior, but that currently don't get marked as # streams, and as a result get the exclusion between concurrent # read()/write() on the same file descriptor. Which doesn't work well for # them. # # The most obvious example if this is /dev/console and /dev/tty, which use # console_fops and tty_fops respectively (and ptmx_fops for the pty master # side). It may be that it's just this that causes problems, but we # clearly weren't ready yet. # # Because there's a number of other likely common cases that don't have # llseek implementations and would seem to act as stream devices: # # /dev/fuse (fuse_dev_operations) # /dev/mcelog (mce_chrdev_ops) # /dev/mei0 (mei_fops) # /dev/net/tun (tun_fops) # /dev/nvme0 (nvme_dev_fops) # /dev/tpm0 (tpm_fops) # /proc/self/ns/mnt (ns_file_operations) # /dev/snd/pcm* (snd_pcm_f_ops[]) # # and while some of these could be trivially automatically detected by the # vfs layer when the character device is opened by just noticing that they # have no read or write operations either, it often isn't that obvious. # # Some character devices most definitely do use the file position, even if # they don't allow seeking: the firmware update code, for example, uses # simple_read_from_buffer() that does use f_pos, but doesn't allow seeking # back and forth. # # We'll revisit this when there's a better way to detect the problem and # fix it (possibly with a coccinelle script to do more of the FMODE_STREAM # annotations). # # Reported-by: Kenneth R. Crudup # Cc: Kirill Smelkov # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux-gcc --version # < /opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux-ld --version # < git log --format=%s --max-count=1 2be7d348fe924f0c5583c6a805bd42cecda93104 # < make -s -j 32 ARCH=sparc64 O=/kisskb/build/linus_sparc64-allmodconfig_sparc64 CROSS_COMPILE=/opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux- allmodconfig # 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 32 ARCH=sparc64 O=/kisskb/build/linus_sparc64-allmodconfig_sparc64 CROSS_COMPILE=/opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux- oldconfig yes: standard output: Broken pipe # make -s -j 32 ARCH=sparc64 O=/kisskb/build/linus_sparc64-allmodconfig_sparc64 CROSS_COMPILE=/opt/cross/kisskb/br-sparc64-full-2016.08-613-ge98b4dd/bin/sparc64-linux- :1511:2: warning: #warning syscall clone3 not implemented [-Wcpp] /kisskb/src/fs/cifs/smb2pdu.c: In function 'SMB2_ioctl_init': /kisskb/src/fs/cifs/smb2pdu.c:2700:19: warning: 'in_data_buf' may be used uninitialized in this function [-Wmaybe-uninitialized] iov[1].iov_base = in_data_buf; ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_zone_nr_conv_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:327:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(zone_nr_conv, uint, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_mbps_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:323:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(mbps, uint, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_index_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:318:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(index, uint, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_hw_queue_depth_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:317:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(hw_queue_depth, uint, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_irqmode_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:316:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(irqmode, uint, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_blocksize_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:315:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(blocksize, uint, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_queue_mode_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:314:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(queue_mode, uint, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_home_node_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:313:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(home_node, uint, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_zone_size_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:326:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(zone_size, ulong, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_cache_size_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:324:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(cache_size, ulong, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_completion_nsec_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:311:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(completion_nsec, ulong, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_size_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:310:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(size, ulong, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_zoned_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:325:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(zoned, bool, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_discard_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:322:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(discard, bool, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_memory_backed_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:321:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(memory_backed, bool, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_use_per_node_hctx_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:320:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(use_per_node_hctx, bool, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_blocking_store': /kisskb/src/drivers/block/null_blk_main.c:291:12: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] dev->NAME = new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:319:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(blocking, bool, NULL); ^ /kisskb/src/drivers/block/null_blk_main.c: In function 'nullb_device_submit_queues_store': /kisskb/src/drivers/block/null_blk_main.c:307:48: warning: 'new_value' may be used uninitialized in this function [-Wmaybe-uninitialized] return set->nr_hw_queues == submit_queues ? 0 : -ENOMEM; ^ /kisskb/src/drivers/block/null_blk_main.c:279:7: note: 'new_value' was declared here TYPE new_value; \ ^ /kisskb/src/drivers/block/null_blk_main.c:312:1: note: in expansion of macro 'NULLB_DEVICE_ATTR' NULLB_DEVICE_ATTR(submit_queues, uint, nullb_apply_submit_queues); ^ /kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c: In function 'sh_mobile_i2c_isr': /kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c:399:26: warning: 'data' may be used uninitialized in this function [-Wmaybe-uninitialized] pd->msg->buf[real_pos] = data; ^ /kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c:372:16: note: 'data' was declared here unsigned char data; ^ /kisskb/src/drivers/input/joystick/analog.c:160:2: warning: #warning Precise timer not defined for this architecture. [-Wcpp] #warning Precise timer not defined for this architecture. ^ In file included from /kisskb/src/include/linux/wait.h:9:0, from /kisskb/src/include/linux/net.h:19, from /kisskb/src/drivers/infiniband/sw/siw/siw_qp_rx.c:8: /kisskb/src/drivers/infiniband/sw/siw/siw_qp_rx.c: In function 'siw_proc_send': /kisskb/src/include/linux/spinlock.h:288:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized] _raw_spin_unlock_irqrestore(lock, flags); \ ^ /kisskb/src/drivers/infiniband/sw/siw/siw_qp_rx.c:335:16: note: 'flags' was declared here unsigned long flags; ^ /kisskb/src/net/netfilter/nf_flow_table_offload.c: In function 'nf_flow_rule_match': /kisskb/src/net/netfilter/nf_flow_table_offload.c:80:21: warning: large integer implicitly truncated to unsigned type [-Woverflow] mask->tcp.flags = TCP_FLAG_RST | TCP_FLAG_FIN; ^ In file included from /kisskb/src/include/linux/rwsem.h:16:0, from /kisskb/src/include/linux/notifier.h:15, from /kisskb/src/include/linux/clk.h:14, from /kisskb/src/drivers/tty/serial/sh-sci.c:24: /kisskb/src/drivers/tty/serial/sh-sci.c: In function 'sci_dma_rx_submit': /kisskb/src/include/linux/spinlock.h:288:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized] _raw_spin_unlock_irqrestore(lock, flags); \ ^ /kisskb/src/drivers/tty/serial/sh-sci.c:1351:16: note: 'flags' was declared here unsigned long flags; ^ /kisskb/src/drivers/net/ethernet/pensando/ionic/ionic_main.c: In function 'ionic_dev_cmd_wait': /kisskb/src/drivers/net/ethernet/pensando/ionic/ionic_main.c:331:6: warning: 'hb' may be used uninitialized in this function [-Wmaybe-uninitialized] int hb; ^ kernel: arch/sparc/boot/image is ready kernel: arch/sparc/boot/zImage is ready warning: same module names found: drivers/char/adi.ko drivers/input/joystick/adi.ko Completed OK # rm -rf /kisskb/build/linus_sparc64-allmodconfig_sparc64 # Build took: 0:15:36.632721