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2020-04-05Merge tag 'powerpc-5.7-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Slightly late as I had to rebase mid-week to insert a bug fix: - A large series from Nick for 64-bit to further rework our exception vectors, and rewrite portions of the syscall entry/exit and interrupt return in C. The result is much easier to follow code that is also faster in general. - Cleanup of our ptrace code to split various parts out that had become badly intertwined with #ifdefs over the years. - Changes to our NUMA setup under the PowerVM hypervisor which should hopefully avoid non-sensical topologies which can lead to warnings from the workqueue code and other problems. - MAINTAINERS updates to remove some of our old orphan entries and update the status of others. - Quite a few other small changes and fixes all over the map. Thanks to: Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen Zhou, Christophe JAILLET, Christophe Leroy, Christoph Hellwig, Clement Courbet, Daniel Axtens, David Gibson, Douglas Miller, Fabiano Rosas, Fangrui Song, Ganesh Goudar, Gautham R. Shenoy, Greg Kroah-Hartman, Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie Halip, Jan Kara, Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger, Laurentiu Tudor, Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira, Michael Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat, Rasmus Villemoes, Ravi Bangoria, Roman Bolshakov, Sam Bobroff, Sandipan Das, Santosh S, Sedat Dilek, Segher Boessenkool, Shilpasri G Bhat, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Tyrel Datwyler, Vaibhav Jain, YueHaibing" * tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits) powerpc: Make setjmp/longjmp signature standard powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_type powerpc: Suppress .eh_frame generation powerpc: Drop -fno-dwarf2-cfi-asm powerpc/32: drop unused ISA_DMA_THRESHOLD powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfaces selftests/powerpc: Fix try-run when source tree is not writable powerpc/vmlinux.lds: Explicitly retain .gnu.hash powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.c powerpc/ptrace: create ppc_gethwdinfo() powerpc/ptrace: create ptrace_get_debugreg() powerpc/ptrace: split out ADV_DEBUG_REGS related functions. powerpc/ptrace: move register viewing functions out of ptrace.c powerpc/ptrace: split out TRANSACTIONAL_MEM related functions. powerpc/ptrace: split out SPE related functions. powerpc/ptrace: split out ALTIVEC related functions. powerpc/ptrace: split out VSX related functions. powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSET powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64 powerpc/ptrace: remove unused header includes ...
2020-04-03Merge tag 'char-misc-5.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the big set of char/misc/other driver patches for 5.7-rc1. Lots of things in here, and it's later than expected due to some reverts to resolve some reported issues. All is now clean with no reported problems in linux-next. Included in here is: - interconnect updates - mei driver updates - uio updates - nvmem driver updates - soundwire updates - binderfs updates - coresight updates - habanalabs updates - mhi new bus type and core - extcon driver updates - some Kconfig cleanups - other small misc driver cleanups and updates As mentioned, all have been in linux-next for a while, and with the last two reverts, all is calm and good" * tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (174 commits) Revert "driver core: platform: Initialize dma_parms for platform devices" Revert "amba: Initialize dma_parms for amba devices" amba: Initialize dma_parms for amba devices driver core: platform: Initialize dma_parms for platform devices bus: mhi: core: Drop the references to mhi_dev in mhi_destroy_device() bus: mhi: core: Initialize bhie field in mhi_cntrl for RDDM capture bus: mhi: core: Add support for reading MHI info from device misc: rtsx: set correct pcr_ops for rts522A speakup: misc: Use dynamic minor numbers for speakup devices mei: me: add cedar fork device ids coresight: do not use the BIT() macro in the UAPI header Documentation: provide IBM contacts for embargoed hardware nvmem: core: remove nvmem_sysfs_get_groups() nvmem: core: use is_bin_visible for permissions nvmem: core: use device_register and device_unregister nvmem: core: add root_only member to nvmem device struct extcon: axp288: Add wakeup support extcon: Mark extcon_get_edev_name() function as exported symbol extcon: palmas: Hide error messages if gpio returns -EPROBE_DEFER dt-bindings: extcon: usbc-cros-ec: convert extcon-usbc-cros-ec.txt to yaml format ...
2020-03-31Merge tag 'tty-5.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial updates from Greg KH: "Here is the big set of TTY / Serial patches for 5.7-rc1 Lots of console fixups and reworking in here, serial core tweaks (doesn't that ever get old, why are we still creating new serial devices?), serial driver updates, line-protocol driver updates, and some vt cleanups and fixes included in here as well. All have been in linux-next with no reported issues" * tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (161 commits) serial: 8250: Optimize irq enable after console write serial: 8250: Fix rs485 delay after console write vt: vt_ioctl: fix use-after-free in vt_in_use() vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console tty: serial: make SERIAL_SPRD depend on COMMON_CLK tty: serial: fsl_lpuart: fix return value checking tty: serial: fsl_lpuart: move dma_request_chan() ARM: dts: tango4: Make /serial compatible with ns16550a ARM: dts: mmp*: Make the serial ports compatible with xscale-uart ARM: dts: mmp*: Fix serial port names ARM: dts: mmp2-brownstone: Don't redeclare phandle references ARM: dts: pxa*: Make the serial ports compatible with xscale-uart ARM: dts: pxa*: Fix serial port names ARM: dts: pxa*: Don't redeclare phandle references serial: omap: drop unused dt-bindings header serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs serial: 8250: 8250_omap: Work around errata causing spurious IRQs with DMA serial: 8250: 8250_omap: Extend driver data to pass FIFO trigger info serial: 8250: 8250_omap: Move locking out from __dma_rx_do_complete() serial: 8250: 8250_omap: Account for data in flight during DMA teardown ...
2020-03-30Merge branch 'pm-qos'Rafael J. Wysocki
* pm-qos: (30 commits) PM: QoS: annotate data races in pm_qos_*_value() Documentation: power: fix pm_qos_interface.rst format warning PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE Documentation: PM: QoS: Update to reflect previous code changes PM: QoS: Update file information comments PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions sound: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*() drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*() x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*() cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request() PM: QoS: Add CPU latency QoS API wrappers PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h PM: QoS: Simplify definitions of CPU latency QoS trace events ...
2020-03-27serial: 8250: Optimize irq enable after console writeLukas Wunner
Commit 7f9803072ff6 ("serial: 8250: Support console on software emulated rs485 ports") amended serial8250_console_write() with rs485 support, but positioned the invocation of ->rs485_stop_tx() after re-enablement of interrupts. The irq handler and ->console_write() are serialized with the port spinlock, so no problem there, but due to the rs485 delay, the irq handler may unnecessarily spin for a while. Avoid that by moving ->rs485_stop_tx() before re-enablement of interrupts, which also mirrors the order at the beginning of serial8250_console_write(). Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/019839cb1f61b01210b6ff9ac9f9079ca77f8411.1585319447.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27serial: 8250: Fix rs485 delay after console writeLukas Wunner
Due to a silly copy-paste mistake, commit 7f9803072ff6 ("serial: 8250: Support console on software emulated rs485 ports") erroneously pauses for the duration of delay_rts_before_send after writing to the console, instead of delay_rts_after_send. Mea culpa. Fixes: 7f9803072ff6 ("serial: 8250: Support console on software emulated rs485 ports") Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/9dd67f33c90d23f7fafa3b81b1e812ddabf9ca24.1585319447.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27vt: vt_ioctl: fix use-after-free in vt_in_use()Eric Biggers
vt_in_use() dereferences console_driver->ttys[i] without proper locking. This is broken because the tty can be closed and freed concurrently. We could fix this by using 'READ_ONCE(console_driver->ttys[i]) != NULL' and skipping the check of tty_struct::count. But, looking at console_driver->ttys[i] isn't really appropriate anyway because even if it is NULL the tty can still be in the process of being closed. Instead, fix it by making vt_in_use() require console_lock() and check whether the vt is allocated and has port refcount > 1. This works since following the patch "vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console" the port refcount is incremented while the vt is open. Reproducer (very unreliable, but it worked for me after a few minutes): #include <fcntl.h> #include <linux/vt.h> int main() { int fd, nproc; struct vt_stat state; char ttyname[16]; fd = open("/dev/tty10", O_RDONLY); for (nproc = 1; nproc < 8; nproc *= 2) fork(); for (;;) { sprintf(ttyname, "/dev/tty%d", rand() % 8); close(open(ttyname, O_RDONLY)); ioctl(fd, VT_GETSTATE, &state); } } KASAN report: BUG: KASAN: use-after-free in vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline] BUG: KASAN: use-after-free in vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657 Read of size 4 at addr ffff888065722468 by task syz-vt2/132 CPU: 0 PID: 132 Comm: syz-vt2 Not tainted 5.6.0-rc5-00130-g089b6d3654916 #13 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014 Call Trace: [...] vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline] vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657 tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660 [...] Allocated by task 136: [...] kzalloc include/linux/slab.h:669 [inline] alloc_tty_struct+0x96/0x8a0 drivers/tty/tty_io.c:2982 tty_init_dev+0x23/0x350 drivers/tty/tty_io.c:1334 tty_open_by_driver drivers/tty/tty_io.c:1987 [inline] tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035 [...] Freed by task 41: [...] kfree+0xbf/0x200 mm/slab.c:3757 free_tty_struct+0x8d/0xb0 drivers/tty/tty_io.c:177 release_one_tty+0x22d/0x2f0 drivers/tty/tty_io.c:1468 process_one_work+0x7f1/0x14b0 kernel/workqueue.c:2264 worker_thread+0x8b/0xc80 kernel/workqueue.c:2410 [...] Fixes: 4001d7b7fc27 ("vt: push down the tty lock so we can see what is left to tackle") Cc: <stable@vger.kernel.org> # v3.4+ Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20200322034305.210082-3-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual consoleEric Biggers
The VT_DISALLOCATE ioctl can free a virtual console while tty_release() is still running, causing a use-after-free in con_shutdown(). This occurs because VT_DISALLOCATE considers a virtual console's 'struct vc_data' to be unused as soon as the corresponding tty's refcount hits 0. But actually it may be still being closed. Fix this by making vc_data be reference-counted via the embedded 'struct tty_port'. A newly allocated virtual console has refcount 1. Opening it for the first time increments the refcount to 2. Closing it for the last time decrements the refcount (in tty_operations::cleanup() so that it happens late enough), as does VT_DISALLOCATE. Reproducer: #include <fcntl.h> #include <linux/vt.h> #include <sys/ioctl.h> #include <unistd.h> int main() { if (fork()) { for (;;) close(open("/dev/tty5", O_RDWR)); } else { int fd = open("/dev/tty10", O_RDWR); for (;;) ioctl(fd, VT_DISALLOCATE, 5); } } KASAN report: BUG: KASAN: use-after-free in con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278 Write of size 8 at addr ffff88806a4ec108 by task syz_vt/129 CPU: 0 PID: 129 Comm: syz_vt Not tainted 5.6.0-rc2 #11 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014 Call Trace: [...] con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278 release_tty+0xa8/0x410 drivers/tty/tty_io.c:1514 tty_release_struct+0x34/0x50 drivers/tty/tty_io.c:1629 tty_release+0x984/0xed0 drivers/tty/tty_io.c:1789 [...] Allocated by task 129: [...] kzalloc include/linux/slab.h:669 [inline] vc_allocate drivers/tty/vt/vt.c:1085 [inline] vc_allocate+0x1ac/0x680 drivers/tty/vt/vt.c:1066 con_install+0x4d/0x3f0 drivers/tty/vt/vt.c:3229 tty_driver_install_tty drivers/tty/tty_io.c:1228 [inline] tty_init_dev+0x94/0x350 drivers/tty/tty_io.c:1341 tty_open_by_driver drivers/tty/tty_io.c:1987 [inline] tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035 [...] Freed by task 130: [...] kfree+0xbf/0x1e0 mm/slab.c:3757 vt_disallocate drivers/tty/vt/vt_ioctl.c:300 [inline] vt_ioctl+0x16dc/0x1e30 drivers/tty/vt/vt_ioctl.c:818 tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660 [...] Fixes: 4001d7b7fc27 ("vt: push down the tty lock so we can see what is left to tackle") Cc: <stable@vger.kernel.org> # v3.4+ Reported-by: syzbot+522643ab5729b0421998@syzkaller.appspotmail.com Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20200322034305.210082-2-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-26tty: serial: make SERIAL_SPRD depend on COMMON_CLKChunyan Zhang
kbuild-test reported an error: config: mips-randconfig-a001-20200321 ... >> drivers/tty/serial/sprd_serial.c:1175: undefined reference to `clk_set_parent' Because some mips Kconfig selects HAVE_CLK but not COMMON_CLK and no clk_set_parent implemented, so the error was exposed. So adding dependence on COMMON_CLK can fix this issue. Fixes: 7ba87cfec71a ("tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> Link: https://lore.kernel.org/r/20200325081427.20312-1-zhang.lyra@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-26tty: serial: fsl_lpuart: fix return value checkingMichael Walle
The return value of lpuart_dma_tx_request() is an negative errno on failure and zero on success. Fixes: 159381df1442f ("tty: serial: fsl_lpuart: fix DMA operation when using IOMMU") Reported-by: Leonard Crestez <leonard.crestez@nxp.com> Signed-off-by: Michael Walle <michael@walle.cc> Reviewed-by: Fugang Duan <fugang.duan@nxp.com> Link: https://lore.kernel.org/r/20200325090658.25967-2-michael@walle.cc Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-26tty: serial: fsl_lpuart: move dma_request_chan()Michael Walle
Move dma_request_chan() out of the atomic context. First this call should not be in the atomic context at all and second the dev_info_once() may cause a hang because because the console takes this spinlock, too. Fixes: 159381df1442f ("tty: serial: fsl_lpuart: fix DMA operation when using IOMMU") Reported-by: Leonard Crestez <leonard.crestez@nxp.com> Signed-off-by: Michael Walle <michael@walle.cc> Reviewed-by: Fugang Duan <fugang.duan@nxp.com> Tested-by: Leonard Crestez <leonard.crestez@nxp.com> Link: https://lore.kernel.org/r/20200325090658.25967-1-michael@walle.cc Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: omap: drop unused dt-bindings headerUwe Kleine-König
The definitons in the dt-binding's gpio header only contains some constants to be used in device trees. It is not relevant for omap-serial (as the gpio API hides the details) and in fact unused so it can just be dropped. Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org> Link: https://lore.kernel.org/r/20200321204031.30369-1-uwe@kleine-koenig.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCsVignesh Raghavendra
UART on K3 SoCs has configurable RX timeout behavior (controlled via EFR2) and better DMA integration. This allows to transfer as larger amount data per DMA transfer compared to older SoCs. Add support for the same. Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20200319110344.21348-7-vigneshr@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: 8250: 8250_omap: Work around errata causing spurious IRQs with DMAVignesh Raghavendra
As per Advisory 27 of AM437x Silicon errata document, Spurious UART interrupts may occur when DMA mode (FCR.DMA_MODE) is enabled. The Interrupt Controller flags that a UART interrupt has occurred; however, the associated IT_PENDING bit remains set to 1, indicating that no interrupt is pending. Acknowledge the spurious interrupts for every occurrence as workaround. Errata is applicable to all TI SoCs with this IP. Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20200319110344.21348-6-vigneshr@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: 8250: 8250_omap: Extend driver data to pass FIFO trigger infoVignesh Raghavendra
Although same 8250 compliant UART IP is reused across different SoC, their integration wrt DMA varies greatly across SoCs. Therefore, different SoC may need to use different FIFO trigger level for DMA event and DMA configuration parameters. Provide a way to pass this information via driver data. This is required to support UART DMA on AM654/J721e SoCs. Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20200319110344.21348-5-vigneshr@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: 8250: 8250_omap: Move locking out from __dma_rx_do_complete()Peter Ujfalusi
Caller functions of __dma_rx_do_complete() already hold rx_dma_lock. Therefore move locking out of the function to avoid need to release and reacquire lock. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20200319110344.21348-4-vigneshr@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: 8250: 8250_omap: Account for data in flight during DMA teardownVignesh Raghavendra
Take into account data stuck in DMA internal buffers before pushing data to higher layer. dma_tx_state has "in_flight_bytes" member that provides this information. Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20200319110344.21348-3-vigneshr@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: 8250: 8250_omap: Terminate DMA before pushing data on RX timeoutVignesh Raghavendra
Terminate and flush DMA internal buffers, before pushing RX data to higher layer. Otherwise, this will lead to data corruption, as driver would end up pushing stale buffer data to higher layer while actual data is still stuck inside DMA hardware and has yet not arrived at the memory. While at that, replace deprecated dmaengine_terminate_all() with dmaengine_terminate_async(). Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20200319110344.21348-2-vigneshr@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: 8250_omap: Fix sleeping function called from invalid context during ↵Peter Ujfalusi
probe When booting j721e the following bug is printed: [ 1.154821] BUG: sleeping function called from invalid context at kernel/sched/completion.c:99 [ 1.154827] in_atomic(): 0, irqs_disabled(): 128, non_block: 0, pid: 12, name: kworker/0:1 [ 1.154832] 3 locks held by kworker/0:1/12: [ 1.154836] #0: ffff000840030728 ((wq_completion)events){+.+.}, at: process_one_work+0x1d4/0x6e8 [ 1.154852] #1: ffff80001214fdd8 (deferred_probe_work){+.+.}, at: process_one_work+0x1d4/0x6e8 [ 1.154860] #2: ffff00084060b170 (&dev->mutex){....}, at: __device_attach+0x38/0x138 [ 1.154872] irq event stamp: 63096 [ 1.154881] hardirqs last enabled at (63095): [<ffff800010b74318>] _raw_spin_unlock_irqrestore+0x70/0x78 [ 1.154887] hardirqs last disabled at (63096): [<ffff800010b740d8>] _raw_spin_lock_irqsave+0x28/0x80 [ 1.154893] softirqs last enabled at (62254): [<ffff800010080c88>] _stext+0x488/0x564 [ 1.154899] softirqs last disabled at (62247): [<ffff8000100fdb3c>] irq_exit+0x114/0x140 [ 1.154906] CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.6.0-rc6-next-20200318-00094-g45e4089b0bd3 #221 [ 1.154911] Hardware name: Texas Instruments K3 J721E SoC (DT) [ 1.154917] Workqueue: events deferred_probe_work_func [ 1.154923] Call trace: [ 1.154928] dump_backtrace+0x0/0x190 [ 1.154933] show_stack+0x14/0x20 [ 1.154940] dump_stack+0xe0/0x148 [ 1.154946] ___might_sleep+0x150/0x1f0 [ 1.154952] __might_sleep+0x4c/0x80 [ 1.154957] wait_for_completion_timeout+0x40/0x140 [ 1.154964] ti_sci_set_device_state+0xa0/0x158 [ 1.154969] ti_sci_cmd_get_device_exclusive+0x14/0x20 [ 1.154977] ti_sci_dev_start+0x34/0x50 [ 1.154984] genpd_runtime_resume+0x78/0x1f8 [ 1.154991] __rpm_callback+0x3c/0x140 [ 1.154996] rpm_callback+0x20/0x80 [ 1.155001] rpm_resume+0x568/0x758 [ 1.155007] __pm_runtime_resume+0x44/0xb0 [ 1.155013] omap8250_probe+0x2b4/0x508 [ 1.155019] platform_drv_probe+0x50/0xa0 [ 1.155023] really_probe+0xd4/0x318 [ 1.155028] driver_probe_device+0x54/0xe8 [ 1.155033] __device_attach_driver+0x80/0xb8 [ 1.155039] bus_for_each_drv+0x74/0xc0 [ 1.155044] __device_attach+0xdc/0x138 [ 1.155049] device_initial_probe+0x10/0x18 [ 1.155053] bus_probe_device+0x98/0xa0 [ 1.155058] deferred_probe_work_func+0x74/0xb0 [ 1.155063] process_one_work+0x280/0x6e8 [ 1.155068] worker_thread+0x48/0x430 [ 1.155073] kthread+0x108/0x138 [ 1.155079] ret_from_fork+0x10/0x18 To fix the bug we need to first call pm_runtime_enable() prior to any pm_runtime calls. Reported-by: Tomi Valkeinen <tomi.valkeinen@ti.com> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Link: https://lore.kernel.org/r/20200320125200.6772-1-peter.ujfalusi@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: 8250: 8250_omap: Fix throttle to call stop_rx()Vignesh Raghavendra
Call stop_rx() to halt reception when throttle is requested. Update unthrottle callback to restart reception. Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20200319103230.16867-3-vigneshr@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: 8250_port: Don't service RX FIFO if throttledVignesh Raghavendra
When port's throttle callback is called, it should stop pushing any more data into TTY buffer to avoid buffer overflow. This means driver has to stop HW from receiving more data and assert the HW flow control. For UARTs with auto HW flow control (such as 8250_omap) manual assertion of flow control line is not possible and only way is to allow RX FIFO to fill up, thus trigger auto HW flow control logic. Therefore make sure that 8250 generic IRQ handler does not drain data when port is stopped (i.e UART_LSR_DR is unset in read_status_mask). Not servicing, RX FIFO would trigger auto HW flow control when FIFO occupancy reaches preset threshold, thus halting RX. Since, error conditions in UART_LSR register are cleared just by reading the register, data has to be drained in case there are FIFO errors, else error information will lost. Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20200319103230.16867-2-vigneshr@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: uartps: Add TACTIVE check in cdns_uart_tx_empty functionRaviteja Narayanam
Make sure that all bytes are transmitted out of Uart by monitoring CDNS_UART_SR_TACTIVE bit as well. Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Acked-by: Maarten Brock <m.brock@vanmierlo.com> Link: https://lore.kernel.org/r/e2514818af5973be291cc117d07739f068b71639.1584610774.git.shubhrajyoti.datta@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: uartps: Remove unconditional wait inside set_termiosRaviteja Narayanam
set_termios function should not wait for the transmit FIFO empty (CDNS_UART_SR_TXEMPTY) unconditionally. The tty layer takes care of it based on the parameter passed (TCSANOW/TCSADRAIN/TCSAFLUSH). Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Link: https://lore.kernel.org/r/536e190dd5bbb474007a67e6323c048288942a28.1584610774.git.shubhrajyoti.datta@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-23Merge 5.6-rc7 into tty-nextGreg Kroah-Hartman
We need the tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-23Merge 5.6-rc7 into char-misc-nextGreg Kroah-Hartman
We need the char/misc driver fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18tty: fix compat TIOCGSERIAL checking wrong function ptrEric Biggers
Commit 77654350306a ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()") changed the compat version of TIOCGSERIAL to start checking for the presence of the ->set_serial function pointer rather than ->get_serial. This appears to be a copy-and-paste error, since ->get_serial is the function pointer that is called as well as the pointer that is checked by the non-compat version of TIOCGSERIAL. Fix this by checking the correct function pointer. Fixes: 77654350306a ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()") Cc: <stable@vger.kernel.org> # v4.20+ Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200224182044.234553-3-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18tty: fix compat TIOCGSERIAL leaking uninitialized memoryEric Biggers
Commit 77654350306a ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()") changed the compat version of TIOCGSERIAL to start copying a whole 'serial_struct32' to userspace rather than individual fields, but failed to initialize all padding and fields -- namely the hole after the 'iomem_reg_shift' field, and the 'reserved' field. Fix this by initializing the struct to zero. [v2: use sizeof, and convert the adjacent line for consistency.] Reported-by: syzbot+8da9175e28eadcb203ce@syzkaller.appspotmail.com Fixes: 77654350306a ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()") Cc: <stable@vger.kernel.org> # v4.20+ Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200224182044.234553-2-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18tty: drop outdated comments about release_tty() lockingEric Biggers
The current version of the TTY code unlocks the tty_struct(s) before release_tty() rather than after. Moreover, tty_unlock_pair() no longer exists. Thus, remove the outdated comments regarding tty_unlock_pair(). Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20200224073359.292795-1-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18tty: n_tracesink: Use the correct style for SPDX License IdentifierNishad Kamdar
This patch corrects the SPDX License Identifier style in header file related to Kernel driver API to route trace data. For C header files Documentation/process/license-rules.rst mandates C-like comments (opposed to C source files where C++ style should be used). Changes made by using a script provided by Joe Perches here: https://lkml.org/lkml/2019/2/7/46. Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com> Link: https://lore.kernel.org/r/20200302143642.GA3335@nishad Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18tty: hvc: Use the correct style for SPDX License IdentifierNishad Kamdar
This patch corrects the SPDX License Identifier style in header file related to the HVC driver. For C header files Documentation/process/license-rules.rst mandates C-like comments (opposed to C source files where C++ style should be used). Changes made by using a script provided by Joe Perches here: https://lkml.org/lkml/2019/2/7/46. Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com> Link: https://lore.kernel.org/r/20200301170419.GA7125@nishad Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18tty: nozomi: Use scnprintf() for avoiding potential buffer overflowTakashi Iwai
Since snprintf() returns the would-be-output size instead of the actual output size, the succeeding calls may go beyond the given buffer limit. Fix it by replacing with scnprintf(). Also rewrite the code in a standard if-form instead of ugly conditional operators. Signed-off-by: Takashi Iwai <tiwai@suse.de> Link: https://lore.kernel.org/r/20200311092905.24362-1-tiwai@suse.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18tty: serial: pch_uart: Use scnprintf() for avoiding potential buffer overflowTakashi Iwai
Since snprintf() returns the would-be-output size instead of the actual output size, the succeeding calls may go beyond the given buffer limit. Fix it by replacing with scnprintf(). Signed-off-by: Takashi Iwai <tiwai@suse.de> Link: https://lore.kernel.org/r/20200311092930.24433-1-tiwai@suse.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18tty: nozomi: fix spelling mistake "reserverd" -> "reserved"Alexandre Belloni
The reserved bits should be named reserved. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20200214141455.20902-1-alexandre.belloni@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18serial: sprd: remove redundant sprd_port cleanupChunyan Zhang
We don't need to cleanup sprd_port anymore, since we've dropped the way of using the sprd_port[] array to get port index. Reviewed-by: Baolin Wang <baolin.wang7@gmail.com> Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> Link: https://lore.kernel.org/r/20200318105049.19623-3-zhang.lyra@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18serial: sprd: getting port index via serial aliases onlyChunyan Zhang
This patch simplifies the process of getting serial port number, with this patch, serial devices must have aliases configured in devicetree. The serial port searched out via sprd_port array maybe wrong if we don't have serial alias defined in devicetree, and specify console with command line, we would get the wrong port number if other serial ports probe failed before console's. So using aliases is mandatory. Reviewed-by: Baolin Wang <baolin.wang7@gmail.com> Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> Link: https://lore.kernel.org/r/20200318105049.19623-2-zhang.lyra@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18tty: serial: Add CONSOLE_POLL support to SiFive UARTVincent Chen
Add CONSOLE_POLL support for future KGDB porting. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Changes since v1: 1. Fix the compile error reported by kbuild test robot Link: https://lore.kernel.org/r/1584492027-23236-1-git-send-email-vincent.chen@sifive.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17serial: 8250_port: Disable DMA operations for kernel consoleAndy Shevchenko
It would be too tricky and error prone to allow DMA operations on kernel console. One of the concern is when DMA is a separate device, for example on Intel CherryTrail platforms, and might need special work around to be functional, see the commit eebb3e8d8aaf ("ACPI / LPSS: override power state for LPSS DMA device") for more information. Another one is that kernel console is used in atomic context, e.g. when printing crucial information to the user (Oops or crash), and DMA may not serve due to power management complications including non-atomic ACPI calls but not limited to it (see above). Besides that, other concerns are described in the commit 84b40e3b57ee ("serial: 8250: omap: Disable DMA for console UART") done for OMAP UART and may be repeated here. Disable any kind of DMA operations on kernel console due to above concerns. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20200217114016.49856-7-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17serial: 8250_port: Don't use power management for kernel consoleAndy Shevchenko
Doing any kind of power management for kernel console is really bad idea. First of all, it runs in poll and atomic mode. This fact attaches a limitation on the functions that might be called. For example, pm_runtime_get_sync() might sleep and thus can't be used. This call needs, for example, to bring the device to powered on state on the system, where the power on sequence may require on-atomic operations, such as Intel Cherrytrail with ACPI enumerated UARTs. That said, on ACPI enabled platforms it might even call firmware for a job. On the other hand pm_runtime_get() doesn't guarantee that device will become powered on fast enough. Besides that, imagine the case when console is about to print a kernel Oops and it's powered off. In such an emergency case calling the complex functions is not the best what we can do, taking into consideration that user wants to see at least something of the last kernel word before it passes away. Here we modify the 8250 console code to prevent runtime power management. Note, there is a behaviour change for OMAP boards. It will require to detach kernel console to become idle. Link: https://lists.openwall.net/linux-kernel/2018/09/29/65 Suggested-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20200217114016.49856-6-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17serial: core: Allow detach and attach serial device for consoleAndy Shevchenko
In the future we would like to disable power management on the serial devices used as kernel consoles to avoid weird behaviour in some cases. However, disabling PM may prevent system to go to deep sleep states, which in its turn leads to the higher power consumption. Tony Lindgren proposed a work around, i.e. allow user to detach such consoles to make PM working again. In case user wants to see what's going on, it also provides a mechanism to attach console back. Link: https://lists.openwall.net/linux-kernel/2018/09/29/65 Suggested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20200217114016.49856-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17Revert "tty: serial: samsung_tty: build it for any platform"Geert Uytterhoeven
This reverts commit 175b558d0efb8b4f33aa7bd2c1b5389b912d3019. When the user configures a kernel without support for Samsung SoCs, it makes no sense to ask the user about enabling "Samsung SoC serial support", as Samsung serial ports can only be found on Samsung SoCs. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20200306102301.16870-1-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17serial: sprd: Fix a dereference warningLanqing Liu
We should validate if the 'sup' is NULL or not before freeing DMA memory, to fix below warning. "drivers/tty/serial/sprd_serial.c:1141 sprd_remove() error: we previously assumed 'sup' could be null (see line 1132)" Fixes: f4487db58eb7 ("serial: sprd: Add DMA mode support") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Lanqing Liu <liuhhome@gmail.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/e2bd92691538e95b04a2c2a728f3292e1617018f.1584325957.git.liuhhome@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17serial: sprd: remove __init from sprd_console_setupChunyan Zhang
The function sprd_console_setup() would be called from .probe() which can be called after freeing __init functions, for example the .probe() would return -EPROBE_DEFER since it depends on clock modules. Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> Reviewed-by: Baolin Wang <baolin.wang7@gmail.com> Link: https://lore.kernel.org/r/20200316101930.9962-3-zhang.lyra@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17serial: sprd: check console via stdout-path in additionChunyan Zhang
The SPRD serial driver need to know which serial port would be used as console in an early period during initialization, the purpose is to keep the console port alive as possible even if there's some error caused by no clock configured under serial devicetree nodes. But with the patch [1], the console port couldn't be identified if missing console command line. So this patch adds using another interface to do check by reading stdout-path. [1] https://lore.kernel.org/lkml/20190826072929.7696-4-zhang.lyra@gmail.com/ Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> Reviewed-by: Baolin Wang <baolin.wang7@gmail.com> Link: https://lore.kernel.org/r/20200316101930.9962-2-zhang.lyra@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17tty: evh_bytechan: Fix out of bounds accessesStephen Rothwell
ev_byte_channel_send() assumes that its third argument is a 16 byte array. Some places where it is called it may not be (or we can't easily tell if it is). Newer compilers have started producing warnings about this, so make sure we actually pass a 16 byte array. There may be more elegant solutions to this, but the driver is quite old and hasn't been updated in many years. The warnings (from a powerpc allyesconfig build) are: In file included from include/linux/byteorder/big_endian.h:5, from arch/powerpc/include/uapi/asm/byteorder.h:14, from include/asm-generic/bitops/le.h:6, from arch/powerpc/include/asm/bitops.h:250, from include/linux/bitops.h:29, from include/linux/kernel.h:12, from include/asm-generic/bug.h:19, from arch/powerpc/include/asm/bug.h:109, from include/linux/bug.h:5, from include/linux/mmdebug.h:5, from include/linux/gfp.h:5, from include/linux/slab.h:15, from drivers/tty/ehv_bytechan.c:24: drivers/tty/ehv_bytechan.c: In function ‘ehv_bc_udbg_putc’: arch/powerpc/include/asm/epapr_hcalls.h:298:20: warning: array subscript 1 is outside array bounds of ‘const char[1]’ [-Warray-bounds] 298 | r6 = be32_to_cpu(p[1]); include/uapi/linux/byteorder/big_endian.h:40:51: note: in definition of macro ‘__be32_to_cpu’ 40 | #define __be32_to_cpu(x) ((__force __u32)(__be32)(x)) | ^ arch/powerpc/include/asm/epapr_hcalls.h:298:7: note: in expansion of macro ‘be32_to_cpu’ 298 | r6 = be32_to_cpu(p[1]); | ^~~~~~~~~~~ drivers/tty/ehv_bytechan.c:166:13: note: while referencing ‘data’ 166 | static void ehv_bc_udbg_putc(char c) | ^~~~~~~~~~~~~~~~ Fixes: dcd83aaff1c8 ("tty/powerpc: introduce the ePAPR embedded hypervisor byte channel driver") Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> [mpe: Trim warnings from change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200109183912.5fcb52aa@canb.auug.org.au
2020-03-16vt: indent switch-case in setterm_command properlyJiri Slaby
Shift cases one level left. This makes the code more readable and some lines need not wrap anymore. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200316065911.11024-3-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16vt: selection, use rounddown() for start/endline computationJiri Slaby
We have a helper called rounddown for these modulo computations. So use it. No functional change intended and "objdump -d" proves that. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200316065911.11024-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16vt: use min() to limit intervalsJiri Slaby
Instead of awkward ternary operator with comparison, use simple min() for blankinterval and vesa_off_interval. No functional change intended and "objdump -d" proves that. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200316065911.11024-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16tty: n_hdlc, remove FILE and LINE from pr_debugJiri Slaby
As Joe suggests, dynamic debug can print module name and line number along with message. So remove __FILE__ and __LINE__ from all those pr_debug calls. Out of curiosity, I measured the savings, 200 bytes of code are gone. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Suggested-by: Joe Perches <joe@perches.com> Link: https://lore.kernel.org/r/20200316064910.4941-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16vt: selection, fix double lock introduced by a mergeJiri Slaby
The merge commit cb05c6c82fb0 (Merge 5.6-rc5 into tty-next) introduced a double lock to set_selection_kernel. vc_sel.lock is locked both in set_selection_kernel and its callee __set_selection_kernel now. Remove the latter. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lore.kernel.org/r/20200316064544.4799-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-14tty: serial: qcom_geni_serial: Don't try to manually disable the consoleDouglas Anderson
The geni serial driver's shutdown code had a special case to call console_stop(). Grepping through the code, it was the only serial driver doing something like this (the only other caller of console_stop() was in serial_core.c). As far as I can tell there's no reason to call console_stop() in the geni code. ...and a good reason _not_ to call it. Specifically if you have an agetty running on the same serial port as the console then killing the agetty kills your console and if you start the agetty again the console doesn't come back. Fixes: c4f528795d1a ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP") Signed-off-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20200313134635.2.I3648fac6c98b887742934146ac2729ecb7232eb1@changeid Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>