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* tty: hvc: Don't enable the RISC-V SBI console by defaultPalmer Dabbelt2024-02-191-3/+5
| | | | | | | | | | | | | | | | | | The new SBI console has the same problem as the old one: there's only one shared backing hardware and no synchronization, so the two drivers end up stepping on each other. This was the same issue the old SBI-0.1 console drivers had, but that was disabled by default when SBI-0.1 was. So just mark the new driver as nonportable. Reported-by: Emil Renner Berthing <kernel@esmil.dk> Fixes: 88ead68e764c ("tty: Add SBI debug console support to HVC SBI driver") Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> Reviewed-by: Paul Walmsley <paul.walmsley@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20240214153429.16484-2-palmer@rivosinc.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'riscv-for-linus-6.8-mw4' of ↵Linus Torvalds2024-01-202-8/+31
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: - Support for tuning for systems with fast misaligned accesses. - Support for SBI-based suspend. - Support for the new SBI debug console extension. - The T-Head CMOs now use PA-based flushes. - Support for enabling the V extension in kernel code. - Optimized IP checksum routines. - Various ftrace improvements. - Support for archrandom, which depends on the Zkr extension. - The build is no longer broken under NET=n, KUNIT=y for ports that don't define their own ipv6 checksum. * tag 'riscv-for-linus-6.8-mw4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (56 commits) lib: checksum: Fix build with CONFIG_NET=n riscv: lib: Check if output in asm goto supported riscv: Fix build error on rv32 + XIP riscv: optimize ELF relocation function in riscv RISC-V: Implement archrandom when Zkr is available riscv: Optimize hweight API with Zbb extension riscv: add dependency among Image(.gz), loader(.bin), and vmlinuz.efi samples: ftrace: Add RISC-V support for SAMPLE_FTRACE_DIRECT[_MULTI] riscv: ftrace: Add DYNAMIC_FTRACE_WITH_DIRECT_CALLS support riscv: ftrace: Make function graph use ftrace directly riscv: select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY lib/Kconfig.debug: Update AS_HAS_NON_CONST_LEB128 comment and name riscv: Restrict DWARF5 when building with LLVM to known working versions riscv: Hoist linker relaxation disabling logic into Kconfig kunit: Add tests for csum_ipv6_magic and ip_fast_csum riscv: Add checksum library riscv: Add checksum header riscv: Add static key for misaligned accesses asm-generic: Improve csum_fold RISC-V: selftests: cbo: Ensure asm operands match constraints ...
| * tty: Add SBI debug console support to HVC SBI driverAtish Patra2024-01-102-8/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | RISC-V SBI specification supports advanced debug console support via SBI DBCN extension. Extend the HVC SBI driver to support it. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20231124070905.1043092-5-apatel@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
* | tty: hvc: convert to u8 and size_tJiri Slaby (SUSE)2023-12-0810-66/+75
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Switch character types to u8 and sizes to size_t. To conform to characters/sizes in the rest of the tty layer. Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Amit Shah <amit@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: linuxppc-dev@lists.ozlabs.org Cc: virtualization@lists.linux.dev Cc: linux-riscv@lists.infradead.org Link: https://lore.kernel.org/r/20231206073712.17776-13-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty: hvc: dcc: Check for TXfull condition while setting up early consoleAyan Kumar Halder2023-12-081-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Refer ARM DDI 0487I.a ID081822, D17.3.8, DBGDTRTX_EL0, "If TXfull is set to 1, set DTRRX and DTRTX to UNKNOWN" Thus one should always check for TXfull condition before hvc can be used as an early console. This is similar to what is being done today in hvc_dcc_console_init() and hvc_dcc_init(). The count 0x4000000 has been obtained from uboot (v2024.01-rc3) drivers/serial/arm_dcc.c "TIMEOUT_COUNT". It reads the dcc status and waits for 0x4000000 times for the TX Fifo to be available before returning an error. Thus, it will prevent DCC to be used as early console. Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com> Link: https://lore.kernel.org/r/20231205123534.3376883-1-ayan.kumar.halder@amd.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty: hvc_console: use flexible array for outbufJiri Slaby (SUSE)2023-11-252-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This means: * move outbuf to the end of struct hvc_struct and convert from pointer to flexible array (the structure is smaller now) * use struct_size() at the allocation site * align outbuf in the struct instead of ALIGN() at kzalloc() And apart from the above, use u8 instead of char (which are the same thanks to -funsigned-char). The former is now preferred over the latter. It makes the code easier to understand. Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Cc: linuxppc-dev@lists.ozlabs.org Link: https://lore.kernel.org/r/20231121092258.9334-12-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty: hvc: hvc_opal: Convert to platform remove callback returning voidUwe Kleine-König2023-11-231-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is ignored (apart from emitting a warning) and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new(), which already returns void. Eventually after all drivers are converted, .remove_new() will be renamed to .remove(). Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Link: https://lore.kernel.org/r/20231105214406.3765906-6-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty: hvc: Make hvc_remove() return no valueUwe Kleine-König2023-11-233-11/+9
|/ | | | | | | | | | | | The function hvc_remove() returns zero unconditionally. Make it return void instead to make it obvious that the caller doesn't need to do any error handling. Accordingly drop the error handling from hvc_opal_remove(). Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Link: https://lore.kernel.org/r/20231105214406.3765906-5-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'tty-6.7-rc1' of ↵Linus Torvalds2023-11-032-13/+28
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty and serial updates from Greg KH: "Here is the big set of tty/serial driver changes for 6.7-rc1. Included in here are: - console/vgacon cleanups and removals from Arnd - tty core and n_tty cleanups from Jiri - lots of 8250 driver updates and cleanups - sc16is7xx serial driver updates - dt binding updates - first set of port lock wrapers from Thomas for the printk fixes coming in future releases - other small serial and tty core cleanups and updates All of these have been in linux-next for a while with no reported issues" * tag 'tty-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (193 commits) serdev: Replace custom code with device_match_acpi_handle() serdev: Simplify devm_serdev_device_open() function serdev: Make use of device_set_node() tty: n_gsm: add copyright Siemens Mobility GmbH tty: n_gsm: fix race condition in status line change on dead connections serial: core: Fix runtime PM handling for pending tx vgacon: fix mips/sibyte build regression dt-bindings: serial: drop unsupported samsung bindings tty: serial: samsung: drop earlycon support for unsupported platforms tty: 8250: Add note for PX-835 tty: 8250: Fix IS-200 PCI ID comment tty: 8250: Add Brainboxes Oxford Semiconductor-based quirks tty: 8250: Add support for Intashield IX cards tty: 8250: Add support for additional Brainboxes PX cards tty: 8250: Fix up PX-803/PX-857 tty: 8250: Fix port count of PX-257 tty: 8250: Add support for Intashield IS-100 tty: 8250: Add support for Brainboxes UP cards tty: 8250: Add support for additional Brainboxes UC cards tty: 8250: Remove UC-257 and UC-431 ...
| * hvc/xen: fix console unplugDavid Woodhouse2023-10-211-8/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On unplug of a Xen console, xencons_disconnect_backend() unconditionally calls free_irq() via unbind_from_irqhandler(), causing a warning of freeing an already-free IRQ: (qemu) device_del con1 [ 32.050919] ------------[ cut here ]------------ [ 32.050942] Trying to free already-free IRQ 33 [ 32.050990] WARNING: CPU: 0 PID: 51 at kernel/irq/manage.c:1895 __free_irq+0x1d4/0x330 It should be using evtchn_put() to tear down the event channel binding, and let the Linux IRQ side of it be handled by notifier_del_irq() through the HVC code. On which topic... xencons_disconnect_backend() should call hvc_remove() *first*, rather than tearing down the event channel and grant mapping while they are in use. And then the IRQ is guaranteed to be freed by the time it's torn down by evtchn_put(). Since evtchn_put() also closes the actual event channel, avoid calling xenbus_free_evtchn() except in the failure path where the IRQ was not successfully set up. However, calling hvc_remove() at the start of xencons_disconnect_backend() still isn't early enough. An unplug request is indicated by the backend setting its state to XenbusStateClosing, which triggers a notification to xencons_backend_changed(), which... does nothing except set its own frontend state directly to XenbusStateClosed without *actually* tearing down the HVC device or, you know, making sure it isn't actively in use. So the backend sees the guest frontend set its state to XenbusStateClosed and stops servicing the interrupt... and the guest spins for ever in the domU_write_console() function waiting for the ring to drain. Fix that one by calling hvc_remove() from xencons_backend_changed() before signalling to the backend that it's OK to proceed with the removal. Tested with 'dd if=/dev/zero of=/dev/hvc1' while telling Qemu to remove the console device. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20231020161529.355083-4-dwmw2@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * hvc/xen: fix error path in xen_hvc_init() to always register frontend driverDavid Woodhouse2023-10-211-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | The xen_hvc_init() function should always register the frontend driver, even when there's no primary console — as there may be secondary consoles. (Qemu can always add secondary consoles, but only the toolstack can add the primary because it's special.) Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20231020161529.355083-3-dwmw2@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * hvc/xen: fix event channel handling for secondary consolesDavid Woodhouse2023-10-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The xencons_connect_backend() function allocates a local interdomain event channel with xenbus_alloc_evtchn(), then calls bind_interdomain_evtchn_to_irq_lateeoi() to bind to that port# on the *remote* domain. That doesn't work very well: (qemu) device_add xen-console,id=con1,chardev=pty0 [ 44.323872] xenconsole console-1: 2 xenbus_dev_probe on device/console/1 [ 44.323995] xenconsole: probe of console-1 failed with error -2 Fix it to use bind_evtchn_to_irq_lateeoi(), which does the right thing by just binding that *local* event channel to an irq. The backend will do the interdomain binding. This didn't affect the primary console because the setup for that is special — the toolstack allocates the guest event channel and the guest discovers it with HVMOP_get_param. Fixes: fe415186b43d ("xen/console: harden hvc_xen against event channel storms") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20231020161529.355083-2-dwmw2@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: hvc: remove set but unused variableBo Liu2023-09-181-2/+0
| | | | | | | | | | | | | | | | | | | | The local variable vdev in hvcs_destruct_port() is set but not used. Remove the variable and related code. Signed-off-by: Bo Liu <liubo03@inspur.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20230908061726.2641-1-liubo03@inspur.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | docs: move powerpc under archCosta Shulyupin2023-10-101-1/+1
|/ | | | | | | | | | | | | and fix all in-tree references. Architecture-specific documentation is being moved into Documentation/arch/ as a way of cleaning up the top-level documentation directory and making the docs hierarchy more closely match the source hierarchy. Signed-off-by: Costa Shulyupin <costa.shul@redhat.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20230826165737.2101199-1-costa.shul@redhat.com
* tty: hvc: convert counts to size_tJiri Slaby (SUSE)2023-08-113-9/+9
| | | | | | | | | | Unify the type of tty_operations::write() counters with the 'count' parameter. I.e. use size_t for them. Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Cc: linuxppc-dev@lists.ozlabs.org Link: https://lore.kernel.org/r/20230810091510.13006-33-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: make tty_operations::write()'s count size_tJiri Slaby (SUSE)2023-08-113-4/+6
| | | | | | | | | Unify with the rest of the code. Use size_t for counts and ssize_t for retval. Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20230810091510.13006-30-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: propagate u8 data to tty_operations::write()Jiri Slaby (SUSE)2023-08-113-5/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Data are now typed as u8. Propagate this change to tty_operations::write(). Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Cc: Richard Henderson <richard.henderson@linaro.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Vaibhav Gupta <vaibhavgupta40@gmail.com> Cc: Jens Taprogge <jens.taprogge@taprogge.org> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Scott Branden <scott.branden@broadcom.com> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: David Lin <dtwlin@gmail.com> Cc: Johan Hovold <johan@kernel.org> Cc: Alex Elder <elder@kernel.org> Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: David Sterba <dsterba@suse.com> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: NXP Linux Team <linux-imx@nxp.com> Cc: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com> Cc: Oliver Neukum <oneukum@suse.com> Cc: Mathias Nyman <mathias.nyman@intel.com> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Johan Hedberg <johan.hedberg@gmail.com> Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com> Link: https://lore.kernel.org/r/20230810091510.13006-28-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: hvsi: remove an extra variable from hvsi_write()Jiri Slaby2023-07-311-2/+1
| | | | | | | | | | | | | 'source' is the same as 'buf'. Rename the parameter ('buf') to 'source' and drop the local variable. Likely, the two were introduced to have a different type. But 'char' and 'unsigned char' are the same in the kernel for a long time. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Cc: linuxppc-dev@lists.ozlabs.org Link: https://lore.kernel.org/r/20230731080244.2698-4-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: Explicitly include correct DT includesRob Herring2023-07-251-1/+1
| | | | | | | | | | | | | | | | The DT of_device.h and of_platform.h date back to the separate of_platform_bus_type before it as merged into the regular platform bus. As part of that merge prepping Arm DT support 13 years ago, they "temporarily" include each other. They also include platform_device.h and of.h. As a result, there's a pretty much random mix of those include files used throughout the tree. In order to detangle these headers and replace the implicit includes with struct declarations, users need to explicitly include the correct includes. Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # for imx Link: https://lore.kernel.org/r/20230724205440.767071-1-robh@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'for-linus-6.3-rc4-tag' of ↵Linus Torvalds2023-03-241-2/+17
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - fix build warning - avoid concurrent accesses to the Xen PV console ring page * tag 'for-linus-6.3-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/PVH: avoid 32-bit build warning when obtaining VGA console info hvc/xen: prevent concurrent accesses to the shared ring
| * hvc/xen: prevent concurrent accesses to the shared ringRoger Pau Monne2023-03-221-2/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hvc machinery registers both a console and a tty device based on the hv ops provided by the specific implementation. Those two interfaces however have different locks, and there's no single locks that's shared between the tty and the console implementations, hence the driver needs to protect itself against concurrent accesses. Otherwise concurrent calls using the split interfaces are likely to corrupt the ring indexes, leaving the console unusable. Introduce a lock to xencons_info to serialize accesses to the shared ring. This is only required when using the shared memory console, concurrent accesses to the hypercall based console implementation are not an issue. Note the conditional logic in domU_read_console() is slightly modified so the notify_daemon() call can be done outside of the locked region: it's an hypercall and there's no need for it to be done with the lock held. Fixes: b536b4b96230 ('xen: use the hvc console infrastructure for Xen console') Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20221130150919.13935-1-roger.pau@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com>
* | hvcs: Synchronize hotplug remove with port freeBrian King2023-02-081-11/+15
| | | | | | | | | | | | | | | | | | | | Synchronizes hotplug remove with the freeing of the port. This ensures we have freed all the memory associated with this port and are not leaking memory. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Link: https://lore.kernel.org/r/20230203155802.404324-6-brking@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | hvcs: Use vhangup in hotplug removeBrian King2023-02-081-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | When hotplug removing an hvcs device, we need to ensure the hangup processing is done prior to exiting the remove function, so use tty_vhangup to do the hangup processing directly rather than using tty_hangup which simply schedules the hangup work for later execution. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Link: https://lore.kernel.org/r/20230203155802.404324-5-brking@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | hvcs: Get reference to tty in removeBrian King2023-02-081-2/+4
| | | | | | | | | | | | | | | | | | Grab a reference to the tty when removing the hvcs to ensure it does not get freed unexpectedly. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Link: https://lore.kernel.org/r/20230203155802.404324-4-brking@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | hvcs: Use driver groups to manage driver attributesBrian King2023-02-081-9/+8
| | | | | | | | | | | | | | | | | | | | | | Rather than manually creating attributes for the hvcs driver, let the driver core do this for us. This also fixes some hotplug remove issues and ensures that cleanup of these attributes is done in the right order. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Link: https://lore.kernel.org/r/20230203155802.404324-3-brking@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | hvcs: Use dev_groups to manage hvcs device attributesBrian King2023-02-081-14/+5
| | | | | | | | | | | | | | | | | | | | | | Use the dev_groups functionality to manage the attribute groups for hvcs devices. This simplifies the code and also eliminates errors coming from kernfs when attempting to remove a console device that is in use. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Link: https://lore.kernel.org/r/20230203155802.404324-2-brking@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | hvcs: Fix hvcs port reference countingBrian King2023-02-021-18/+0
| | | | | | | | | | | | | | | | | | | | | | The hvcs driver only ever gets two references to the port. One at initialization time, and one at install time. Remove the code that was trying to do multiple port puts for each open, which would result in more puts than gets. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Link: https://lore.kernel.org/r/20230201195743.303163-2-brking@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty: Call ->dtr_rts() parameter active consistentlyIlpo Järvinen2023-01-192-4/+4
| | | | | | | | | | | | | | | | | | | | | | Convert various parameter names for ->dtr_rts() and related functions from onoff, on, and raise to active. Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230117090358.4796-12-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty: Convert ->dtr_rts() to take bool argumentIlpo Järvinen2023-01-193-5/+5
|/ | | | | | | | | | | | | | | | Convert the raise/on parameter in ->dtr_rts() to bool through the callchain. The parameter is used like bool. In USB serial, there remains a few implicit bool -> larger type conversions because some devices use u8 in their control messages. In moxa_tiocmget(), dtr variable was reused for line status which requires int so use a separate variable for status. Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230117090358.4796-8-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'for-linus-6.2-rc4-tag' of ↵Linus Torvalds2023-01-121-19/+31
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - two cleanup patches - a fix of a memory leak in the Xen pvfront driver - a fix of a locking issue in the Xen hypervisor console driver * tag 'for-linus-6.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/pvcalls: free active map buffer on pvcalls_front_free_map hvc/xen: lock console list traversal x86/xen: Remove the unused function p2m_index() xen: make remove callback of xen driver void returned
| * hvc/xen: lock console list traversalRoger Pau Monne2023-01-091-17/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The currently lockless access to the xen console list in vtermno_to_xencons() is incorrect, as additions and removals from the list can happen anytime, and as such the traversal of the list to get the private console data for a given termno needs to happen with the lock held. Note users that modify the list already do so with the lock taken. Adjust current lock takers to use the _irq{save,restore} helpers, since the context in which vtermno_to_xencons() is called can have interrupts disabled. Use the _irq{save,restore} set of helpers to switch the current callers to disable interrupts in the locked region. I haven't checked if existing users could instead use the _irq variant, as I think it's safer to use _irq{save,restore} upfront. While there switch from using list_for_each_entry_safe to list_for_each_entry: the current entry cursor won't be removed as part of the code in the loop body, so using the _safe variant is pointless. Fixes: 02e19f9c7cac ('hvc_xen: implement multiconsole support') Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/20221130163611.14686-1-roger.pau@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com>
| * xen: make remove callback of xen driver void returnedDawei Li2022-12-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit fc7a6209d571 ("bus: Make remove callback return void") forces bus_type::remove be void-returned, it doesn't make much sense for any bus based driver implementing remove callbalk to return non-void to its caller. This change is for xen bus based drivers. Acked-by: Juergen Gross <jgross@suse.com> Signed-off-by: Dawei Li <set_pte_at@outlook.com> Link: https://lore.kernel.org/r/TYCP286MB23238119AB4DF190997075C9CAE39@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM Signed-off-by: Juergen Gross <jgross@suse.com>
* | Merge tag 'tty-6.2-rc1' of ↵Linus Torvalds2022-12-161-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver updates from Greg KH: "Here is the "big" set of tty/serial driver changes for 6.2-rc1. As in previous kernel releases, nothing big here at all, just some small incremental serial/tty layer cleanups and some individual driver additions and fixes. Highlights are: - serial helper macros from Jiri Slaby to reduce the amount of duplicated code in serial drivers - api cleanups and consolidations from Ilpo Järvinen in lots of serial drivers - the usual set of n_gsm fixes from Daniel Starke as that code gets exercised more - TIOCSTI is finally able to be disabled if requested (security hardening feature from Kees Cook) - fsl_lpuart driver fixes and features added - other small serial driver additions and fixes All of these have been in linux-next for a while with no reported problems" * tag 'tty-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (97 commits) serial: atmel: don't stop the transmitter when doing PIO serial: atmel: cleanup atmel_start+stop_tx() tty: serial: fsl_lpuart: switch to new dmaengine_terminate_* API serial: sunsab: Fix error handling in sunsab_init() serial: altera_uart: fix locking in polling mode serial: pch: Fix PCI device refcount leak in pch_request_dma() tty: serial: fsl_lpuart: Use pm_ptr() to avoid need to make pm __maybe_unused tty: serial: fsl_lpuart: Add runtime pm support tty: serial: fsl_lpuart: enable wakeup source for lpuart serdev: Replace poll loop by readx_poll_timeout() macro tty: synclink_gt: unwind actions in error path of net device open serial: stm32: move dma_request_chan() before clk_prepare_enable() dt-bindings: serial: xlnx,opb-uartlite: Drop 'contains' from 'xlnx,use-parity' serial: pl011: Do not clear RX FIFO & RX interrupt in unthrottle. serial: amba-pl011: avoid SBSA UART accessing DMACR register tty: serial: altera_jtaguart: remove struct altera_jtaguart tty: serial: altera_jtaguart: use uart_port::read_status_mask tty: serial: altera_jtaguart: remove unused altera_jtaguart::sigs tty: serial: altera_jtaguart: remove flag from altera_jtaguart_rx_chars() n_tty: Rename tail to old_tail in n_tty_read() ...
| * | tty: hvc: make hvc_rtas_dev staticruanjinjie2022-11-031-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | The symbol is not used outside of the file, so mark it static. Fixes the following warning: drivers/tty/hvc/hvc_rtas.c:29:19: warning: symbol 'hvc_rtas_dev' was not declared. Should it be static? Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: ruanjinjie <ruanjinjie@huawei.com> Link: https://lore.kernel.org/r/20221019064412.3759874-1-ruanjinjie@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* / tty: hvc: use console_is_registered()John Ogness2022-12-021-2/+2
|/ | | | | | | | | | It is not reliable to check for CON_ENABLED in order to identify if a console is registered. Use console_is_registered() instead. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-26-john.ogness@linutronix.de
* tty: hvc: remove HVC_IUCV_MAGICнаб2022-09-221-6/+5
| | | | | | | | | | | | | | | According to Greg, in the context of magic numbers as defined in magic-number.rst, "the tty layer should not need this and I'll gladly take patches" This stretches that definition slightly, since it multiplexes it with the terminal number as a constant offset, but is equivalent Acked-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz> Ref: https://lore.kernel.org/linux-doc/YyMlovoskUcHLEb7@kroah.com/ Link: https://lore.kernel.org/r/8c8a2c9dfc1bfbe6ef3f3237368e483865fc1c29.1663288066.git.nabijaczleweli@nabijaczleweli.xyz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* termios: start unifying non-UAPI parts of asm/termios.hAl Viro2022-09-091-0/+1
| | | | | | | | | | | | * new header (linut/termios_internal.h), pulled by the users of those suckers * defaults for INIT_C_CC and externs for conversion helpers moved over there * remove termios-base.h (empty now) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Link: https://lore.kernel.org/r/YxDmptU7dNGZ+/Hn@ZenIV Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: move from strlcpy with unused retval to strscpyWolfram Sang2022-08-301-1/+1
| | | | | | | | | | | | Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Link: https://lore.kernel.org/r/20220818210113.7469-1-wsa+renesas@sang-engineering.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'for-linus-5.19-rc1b-tag' of ↵Linus Torvalds2022-06-041-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull more xen updates from Juergen Gross: "Two cleanup patches for Xen related code and (more important) an update of MAINTAINERS for Xen, as Boris Ostrovsky decided to step down" * tag 'for-linus-5.19-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: replace xen_remap() with memremap() MAINTAINERS: Update Xen maintainership xen: switch gnttab_end_foreign_access() to take a struct page pointer
| * xen: replace xen_remap() with memremap()Juergen Gross2022-06-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xen_remap() is used to establish mappings for frames not under direct control of the kernel: for Xenstore and console ring pages, and for grant pages of non-PV guests. Today xen_remap() is defined to use ioremap() on x86 (doing uncached mappings), and ioremap_cache() on Arm (doing cached mappings). Uncached mappings for those use cases are bad for performance, so they should be avoided if possible. As all use cases of xen_remap() don't require uncached mappings (the mapped area is always physical RAM), a mapping using the standard WB cache mode is fine. As sparse is flagging some of the xen_remap() use cases to be not appropriate for iomem(), as the result is not annotated with the __iomem modifier, eliminate xen_remap() completely and replace all use cases with memremap() specifying the MEMREMAP_WB caching mode. xen_unmap() can be replaced with memunmap(). Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Acked-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/20220530082634.6339-1-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
* | tty: hvc: dcc: Bind driver to CPU core0 for reads and writesShanker Donthineni2022-05-052-4/+209
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some external debuggers do not handle reads/writes from/to DCC on secondary cores. Each core has its own DCC device registers, so when a core reads or writes from/to DCC, it only accesses its own DCC device. Since kernel code can run on any core, every time the kernel wants to write to the console, it might write to a different DCC. In SMP mode, external debugger creates multiple windows, and each window shows the DCC output only from that core's DCC. The result is that console output is either lost or scattered across windows. Selecting this debug option will enable code that serializes all console input and output to core 0. The DCC driver will create input and output FIFOs that all cores will use. Reads and writes from/to DCC are handled by a workqueue that runs only core 0. This is a debug feature to be used only in early stage development where debug serial console support would not be present. It disables PM feature like CPU hotplug and is not suitable for production environment. Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Acked-by: Adam Wallis <awallis@codeaurora.org> Signed-off-by: Timur Tabi <timur@codeaurora.org> Signed-off-by: Elliot Berman <eberman@codeaurora.org> Signed-off-by: Sai Prakash Ranjan <quic_saipraka@quicinc.com> Link: https://lore.kernel.org/r/20220428090858.14489-1-quic_saipraka@quicinc.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty: hvcs: simplify if-if to if-elseWan Jiabing2022-04-261-3/+2
| | | | | | | | | | | | | | | | Use if and else instead of if(A) and if (!A) and fix a coding style. Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Link: https://lore.kernel.org/r/20220424091310.98780-1-wanjiabing@vivo.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty/hvc_opal: simplify if-if to if-elseWan Jiabing2022-04-261-2/+2
| | | | | | | | | | | | | | | | | | Use if and else instead of if(A) and if (!A). Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Link: https://lore.kernel.org/r/20220426071041.168282-1-wanjiabing@vivo.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty: hvc: Prepare cleanup of powerpc's asm/prom.hChristophe Leroy2022-04-153-3/+3
|/ | | | | | | | | | | | powerpc's asm/prom.h brings some headers that it doesn't need itself. In order to clean it up, first add missing headers in users of asm/prom.h Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Link: https://lore.kernel.org/r/8b3dbd25bbeb7949e1b0a2170fee7b9cc5a6f806.1648833418.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: hvc: fix return value of __setup handlerRandy Dunlap2022-03-181-1/+3
| | | | | | | | | | | | | | | | | | | | | __setup() handlers should return 1 to indicate that the boot option has been handled or 0 to indicate that it was not handled. Add a pr_warn() message if the option value is invalid and then always return 1. Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Fixes: 86b40567b917 ("tty: replace strict_strtoul() with kstrtoul()") Cc: Jingoo Han <jg1.han@samsung.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Julian Wiedmann <jwi@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: linuxppc-dev@lists.ozlabs.org Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20220308024228.20477-1-rdunlap@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: make uart_console_write->putchar()'s character an unsigned charJiri Slaby2022-03-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, uart_console_write->putchar's second parameter (the character) is of type int. It makes little sense, provided uart_console_write() accepts the input string as "const char *s" and passes its content -- the characters -- to putchar(). So switch the character's type to unsigned char. We don't use char as that is signed on some platforms. That would cause troubles for drivers which (implicitly) cast the char to u16 when writing to the device. Sign extension would happen in that case and the value written would be completely different to the provided char. DZ is an example of such a driver -- on MIPS, it uses u16 for dz_out in dz_console_putchar(). Note we do the char -> uchar conversion implicitly in uart_console_write(). Provided we do not change size of the data type, sign extension does not happen there, so the problem is void. This makes the types consistent and unified with the rest of the uart layer, which uses unsigned char in most places already. One exception is xmit_buf, but that is going to be converted later. Cc: Paul Cercueil <paul@crapouillou.net> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Ludovic Desroches <ludovic.desroches@microchip.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: "Maciej W. Rozycki" <macro@orcam.me.uk> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: NXP Linux Team <linux-imx@nxp.com> Cc: Karol Gugala <kgugala@antmicro.com> Cc: Mateusz Holenko <mholenko@antmicro.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Neil Armstrong <narmstrong@baylibre.com> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Jerome Brunet <jbrunet@baylibre.com> Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Cc: Taichi Sugaya <sugaya.taichi@socionext.com> Cc: Takao Orito <orito.takao@socionext.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: "Andreas Färber" <afaerber@suse.de> Cc: Manivannan Sadhasivam <mani@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Andy Gross <agross@kernel.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Cc: Orson Zhai <orsonzhai@gmail.com> Cc: Baolin Wang <baolin.wang7@gmail.com> Cc: Chunyan Zhang <zhang.lyra@gmail.com> Cc: Patrice Chotard <patrice.chotard@foss.st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Peter Korsgaard <peter@korsgaard.com> Cc: Michal Simek <michal.simek@xilinx.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> [atmel_serial] Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Paul Cercueil <paul@crapouillou.net> Acked-by: Neil Armstrong <narmstrong@baylibre.com> # meson_serial Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20220303080831.21783-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xen/console: harden hvc_xen against event channel stormsJuergen Gross2021-12-161-3/+27
| | | | | | | | | | | | | | | | | | | | | | | | | The Xen console driver is still vulnerable for an attack via excessive number of events sent by the backend. Fix that by using a lateeoi event channel. For the normal domU initial console this requires the introduction of bind_evtchn_to_irq_lateeoi() as there is no xenbus device available at the time the event channel is bound to the irq. As the decision whether an interrupt was spurious or not requires to test for bytes having been read from the backend, move sending the event into the if statement, as sending an event without having found any bytes to be read is making no sense at all. This is part of XSA-391 Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> --- V2: - slightly adapt spurious irq detection (Jan Beulich) V3: - fix spurious irq detection (Jan Beulich)
* xen: flag hvc_xen to be not essential for system bootJuergen Gross2021-11-231-0/+1
| | | | | | | | | | The Xen pv console driver is not essential for boot. Set the respective flag. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20211022064800.14978-4-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
* Revert "tty: hvc: pass DMA capable memory to put_chars()"Greg Kroah-Hartman2021-10-262-41/+16
| | | | | | | | | | | | This reverts commit 0986d7bc5598f5df30e3db777d00e73890c97627. It still has some issues and needs to be dropped at this point in time. Link: https://lore.kernel.org/r/208f7a41-a9fa-630c-cb44-c37c503f3a72@kernel.org Reported-by: Jiri Slaby <jirislaby@kernel.org> Cc: Xianting Tian <xianting.tian@linux.alibaba.com> Cc: Shile Zhang <shile.zhang@linux.alibaba.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: hvc: pass DMA capable memory to put_chars()Xianting Tian2021-10-212-16/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As well known, hvc backend can register its opertions to hvc backend. the operations contain put_chars(), get_chars() and so on. Some hvc backend may do dma in its operations. eg, put_chars() of virtio-console. But in the code of hvc framework, it may pass DMA incapable memory to put_chars() under a specific configuration, which is explained in commit c4baad5029(virtio-console: avoid DMA from stack): 1, c[] is on stack, hvc_console_print(): char c[N_OUTBUF] __ALIGNED__; cons_ops[index]->put_chars(vtermnos[index], c, i); 2, ch is on stack, static void hvc_poll_put_char(,,char ch) { struct tty_struct *tty = driver->ttys[0]; struct hvc_struct *hp = tty->driver_data; int n; do { n = hp->ops->put_chars(hp->vtermno, &ch, 1); } while (n <= 0); } Commit c4baad5029 is just the fix to avoid DMA from stack memory, which is passed to virtio-console by hvc framework in above code. But I think the fix is aggressive, it directly uses kmemdup() to alloc new buffer from kmalloc area and do memcpy no matter the memory is in kmalloc area or not. But most importantly, it should better be fixed in the hvc framework, by changing it to never pass stack memory to the put_chars() function in the first place. Otherwise, we still face the same issue if a new hvc backend using dma added in the furture. In this patch, add 'char cons_outbuf[]' as part of 'struct hvc_struct', so hp->cons_outbuf is no longer the stack memory, we can use it in above cases safely. We also add lock to protect cons_outbuf instead of using the global lock of hvc. Introduce another array(cons_hvcs[]) for hvc pointers next to the cons_ops[] and vtermnos[] arrays. With the array, we can easily find hvc's cons_outbuf and its lock. With the patch, we can revert the fix c4baad5029. Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com> Signed-off-by: Shile Zhang <shile.zhang@linux.alibaba.com> Link: https://lore.kernel.org/r/20211015024658.1353987-3-xianting.tian@linux.alibaba.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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