#
f32fcbed |
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06-Dec-2023 |
Jiri Slaby (SUSE) <jirislaby@kernel.org> |
tty: hvc: convert to u8 and size_t 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>
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#
a30badfd |
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20-Oct-2023 |
David Woodhouse <dwmw@amazon.co.uk> |
hvc/xen: fix console unplug 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>
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#
2704c9a5 |
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20-Oct-2023 |
David Woodhouse <dwmw@amazon.co.uk> |
hvc/xen: fix error path in xen_hvc_init() to always register frontend driver 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>
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#
ef5dd8ec |
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20-Oct-2023 |
David Woodhouse <dwmw@amazon.co.uk> |
hvc/xen: fix event channel handling for secondary consoles 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>
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#
6214894f |
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30-Nov-2022 |
Roger Pau Monne <roger.pau@citrix.com> |
hvc/xen: prevent concurrent accesses to the shared ring 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>
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#
c0dccad8 |
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30-Nov-2022 |
Roger Pau Monne <roger.pau@citrix.com> |
hvc/xen: lock console list traversal 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>
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#
7cffcade |
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13-Dec-2022 |
Dawei Li <set_pte_at@outlook.com> |
xen: make remove callback of xen driver void returned 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>
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#
41925b10 |
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30-May-2022 |
Juergen Gross <jgross@suse.com> |
xen: replace xen_remap() with memremap() 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>
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#
fe415186 |
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16-Dec-2021 |
Juergen Gross <jgross@suse.com> |
xen/console: harden hvc_xen against event channel storms 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)
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#
02391434 |
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22-Oct-2021 |
Juergen Gross <jgross@suse.com> |
xen: flag hvc_xen to be not essential for system boot 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>
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#
42bc9716 |
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30-Sep-2021 |
Jan Beulich <jbeulich@suse.com> |
xen/x86: make "earlyprintk=xen" work for HVM/PVH DomU xenboot_write_console() is dealing with these quite fine so I don't see why xenboot_console_setup() would return -ENOENT in this case. Adjust documentation accordingly. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/3d212583-700e-8b2d-727a-845ef33ac265@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
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#
adf330a7 |
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30-Sep-2021 |
Jan Beulich <jbeulich@suse.com> |
xen/x86: make "earlyprintk=xen" work better for PVH Dom0 The xen_hvm_early_write() path better wouldn't be taken in this case; while port 0xE9 can be used, the hypercall path is quite a bit more efficient. Put that first, as it may also work for DomU-s (see also xen_raw_console_write()). While there also bail from the function when the first domU_write_console() failed - later ones aren't going to succeed. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/4fd89dcb-cfc5-c740-2e94-bb271e432d3e@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
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#
e679004d |
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07-Jul-2021 |
Juergen Gross <jgross@suse.com> |
tty: hvc: replace BUG_ON() with negative return value Xen frontends shouldn't BUG() in case of illegal data received from their backends. So replace the BUG_ON()s when reading illegal data from the ring page with negative return values. Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20210707091045.460-1-jgross@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
df561f66 |
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23-Aug-2020 |
Gustavo A. R. Silva <gustavoars@kernel.org> |
treewide: Use fallthrough pseudo-keyword Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
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#
6f2fdb29 |
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19-Jun-2020 |
Sergey Senozhatsky <sergey.senozhatsky@gmail.com> |
hvc: unify console setup naming Use the 'common' foo_console_setup() naming scheme. There are 71 foo_console_setup() callbacks and only one foo_setup_console(). Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20200619172240.754910-1-sergey.senozhatsky@gmail.com
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#
d56f00fd |
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25-Feb-2019 |
Gustavo A. R. Silva <gustavo@embeddedor.com> |
tty: hvc_xen: Mark expected switch fall-through In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. This patch fixes the following warning: drivers/tty/hvc/hvc_xen.c: In function ‘xencons_backend_changed’: drivers/tty/hvc/hvc_xen.c:493:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (dev->state == XenbusStateClosed) ^ drivers/tty/hvc/hvc_xen.c:496:2: note: here case XenbusStateClosing: ^~~~ Warning level 3 was used: -Wimplicit-fallthrough=3 Notice that, in this particular case, the code comment is modified in accordance with what GCC is expecting to find. This patch is part of the ongoing efforts to enable -Wimplicit-fallthrough Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
a9f96f01 |
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06-Nov-2017 |
Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
tty: hvc: Remove redundant license text Now that the SPDX tag is in all tty files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Jiri Slaby <jslaby@suse.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Chris Metcalf <cmetcalf@mellanox.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
e3b3d0f5 |
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06-Nov-2017 |
Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
tty: add SPDX identifiers to all remaining files in drivers/tty/ It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the drivers/tty files files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Jiri Slaby <jslaby@suse.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: David Sterba <dsterba@suse.com> Cc: James Hogan <jhogan@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Eric Anholt <eric@anholt.net> Cc: Stefan Wahren <stefan.wahren@i2se.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Ray Jui <rjui@broadcom.com> Cc: Scott Branden <sbranden@broadcom.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Joachim Eastwood <manabian@gmail.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: "Maciej W. Rozycki" <macro@linux-mips.org> Cc: "Uwe Kleine-König" <kernel@pengutronix.de> Cc: Pat Gefre <pfg@sgi.com> Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Sylvain Lemieux <slemieux.tyco@gmail.com> Cc: Carlo Caione <carlo@caione.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Andy Gross <andy.gross@linaro.org> Cc: David Brown <david.brown@linaro.org> Cc: "Andreas Färber" <afaerber@suse.de> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Laxman Dewangan <ldewangan@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Barry Song <baohua@kernel.org> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Peter Korsgaard <jacmet@sunsite.dk> Cc: Timur Tabi <timur@tabi.org> Cc: Tony Prisk <linux@prisktech.co.nz> Cc: Michal Simek <michal.simek@xilinx.com> Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Jiri Slaby <jslaby@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
a4d7b75b |
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24-Feb-2016 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
hvc_xen: make early_printk work with HVM guests Refactor the existing code in xen_raw_console_write to get the generic early_printk console work with HVM guests. Take the opportunity to replace the outb loop with a single outsb call to reduce the number of vmexit. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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#
5de738b3 |
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24-Feb-2016 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
hvc_xen: fix xenboot for DomUs The xenboot early console has been partially broken for DomU for a long time: the output would only go to the hypervisor via hypercall (HYPERVISOR_console_io), while it wouldn't actually go to the DomU console. The reason is that domU_write_console would return early as no xencons structs are configured for it. Add an appropriate xencons struct for xenboot from the xenboot setup callback. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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#
16e506ef |
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24-Feb-2016 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
hvc_xen: add earlycon support Introduce EARLYCON support in hvc_xen, useful for early debugging on arm and arm64, where xen early_printk is not available. It is different from xenboot_write_console on x86 in two ways: - it does not return if !xen_pv_domain(), not only because ARM guests are xen_hvm_domain(), but also because we want to capture all the early boot messages, before xen support is discovered - it does not try to print to the domU console at all, because xen support will only be discovered at a later point Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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#
54573c4a |
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30-Dec-2015 |
Julia Lawall <Julia.Lawall@lip6.fr> |
xen/hvc: constify hv_ops structures These hv_ops structures are never modified, so declare them as const. Most were const already. Done with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
e36ae343 |
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25-Jan-2016 |
Arnd Bergmann <arnd@arndb.de> |
tty: hvc_xen: hide xen_console_remove when unused xencons_disconnect_backend() is only called from xen_console_remove(), which is conditionally compiled, so we get a harmless warning when CONFIG_HVC_XEN_FRONTEND is unset: hvc/hvc_xen.c:350:12: error: 'xen_console_remove' defined but not used [-Werror=unused-function] This moves the function down into the same #ifdef section to silence the warning. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
9652c080 |
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05-May-2015 |
Julien Grall <julien.grall@citrix.com> |
tty/hvc: xen: Use xen page definition The console ring is always based on the page granularity of Xen. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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#
859e3267 |
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07-Aug-2015 |
Julien Grall <julien.grall@citrix.com> |
hvc/xen: Further s/MFN/GFN clean-up HVM_PARAM_CONSOLE_PFN is used to retrieved the console PFN for HVM guest. It returns a PFN (aka GFN) and not a MFN. Furthermore, use directly virt_to_gfn for both PV and HVM domain rather than doing a special case for each of the them. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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#
0df4f266 |
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07-Aug-2015 |
Julien Grall <julien.grall@citrix.com> |
xen: Use correctly the Xen memory terminologies Based on include/xen/mm.h [1], Linux is mistakenly using MFN when GFN is meant, I suspect this is because the first support for Xen was for PV. This resulted in some misimplementation of helpers on ARM and confused developers about the expected behavior. For instance, with pfn_to_mfn, we expect to get an MFN based on the name. Although, if we look at the implementation on x86, it's returning a GFN. For clarity and avoid new confusion, replace any reference to mfn with gfn in any helpers used by PV drivers. The x86 code will still keep some reference of pfn_to_mfn which may be used by all kind of guests No changes as been made in the hypercall field, even though they may be invalid, in order to keep the same as the defintion in xen repo. Note that page_to_mfn has been renamed to xen_page_to_gfn to avoid a name to close to the KVM function gfn_to_page. Take also the opportunity to simplify simple construction such as pfn_to_mfn(page_to_pfn(page)) into xen_page_to_gfn. More complex clean up will come in follow-up patches. [1] http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=e758ed14f390342513405dd766e874934573e6cb Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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c4ace5da |
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28-May-2015 |
Jan Beulich <JBeulich@suse.com> |
hvc_xen: avoid uninitialized variable warning Older compilers don't recognize that "v" can't be used uninitialized; other code using hvm_get_parameter() zeros the value too, so follow suit here. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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77bb3dfd |
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19-May-2015 |
David Vrabel <david.vrabel@citrix.com> |
xen/events: don't bind non-percpu VIRQs with percpu chip A non-percpu VIRQ (e.g., VIRQ_CONSOLE) may be freed on a different VCPU than it is bound to. This can result in a race between handle_percpu_irq() and removing the action in __free_irq() because handle_percpu_irq() does not take desc->lock. The interrupt handler sees a NULL action and oopses. Only use the percpu chip/handler for per-CPU VIRQs (like VIRQ_TIMER). # cat /proc/interrupts | grep virq 40: 87246 0 xen-percpu-virq timer0 44: 0 0 xen-percpu-virq debug0 47: 0 20995 xen-percpu-virq timer1 51: 0 0 xen-percpu-virq debug1 69: 0 0 xen-dyn-virq xen-pcpu 74: 0 0 xen-dyn-virq mce 75: 29 0 xen-dyn-virq hvc_console Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: <stable@vger.kernel.org>
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b9d934f2 |
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29-Apr-2015 |
Boris Ostrovsky <boris.ostrovsky@oracle.com> |
xen/console: Update console event channel on resume After a resume the hypervisor/tools may change console event channel number. We should re-query it. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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95afae48 |
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08-Sep-2014 |
David Vrabel <david.vrabel@citrix.com> |
xen: remove DEFINE_XENBUS_DRIVER() macro The DEFINE_XENBUS_DRIVER() macro looks a bit weird and causes sparse errors. Replace the uses with standard structure definitions instead. This is similar to pci and usb device registration. Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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fb498df0 |
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12-Aug-2014 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
xen_hvc: no reason to write the type key on xenstore The backend type is chosen by the toolstack. Regardless, the frontend should not care, especially given that it cannot have an effect as the backend is started before this code is run. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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4fedd0bf |
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15-Jan-2014 |
Paul Gortmaker <paul.gortmaker@windriver.com> |
drivers/tty/hvc: don't use module_init in non-modular hyp. console code The HVC_OPAL/RTAS/UDBG/XEN options are all bool, and hence their support is either present or absent. It will never be modular, so using module_init as an alias for __initcall is rather misleading. Fix this up now, so that we can relocate module_init from init.h into module.h in the future. If we don't do this, we'd have to add module.h to obviously non-modular code, and that would be a worse thing. Note that direct use of __initcall is discouraged, vs. one of the priority categorized subgroups. As __initcall gets mapped onto device_initcall, our use of device_initcall directly in this change means that the runtime impact is zero -- it will remain at level 6 in initcall ordering. Also the __exitcall functions have been outright deleted since they are only ever of interest to UML, and UML will never be using any of this code. Cc: Richard Weinberger <richard@nod.at> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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a9fbf4d5 |
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01-Oct-2013 |
David Vrabel <david.vrabel@citrix.com> |
xen/hvc: allow xenboot console to be used again Commit d0380e6c3c0f6edb986d8798a23acfaf33d5df23 (early_printk: consolidate random copies of identical code) added in 3.10 introduced a check for con->index == -1 in early_console_register(). Initialize index to -1 for the xenboot console so earlyprintk=xen works again. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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04b772d2 |
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27-Sep-2013 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/hvc: If we use xen_raw_printk let it also work on HVM guests. The xen_raw_printk works great for debugging purposes. We use for PV guests and we can also use it for HVM guests. However, for HVM guests we have a fallback of using the 0xe9 port in case the hypervisor does not support an HVM guest of using the console_io hypercall. As such lets use 0xe9 during early bootup, and once the hyper-page is setup and if the console_io hypercall is supported - use that. Otherwise we will fallback to using the 0xe9 after early bootup. We also alter the return value for dom0_write_console to return an error value instead of zero. The HVC API has been supporting returning error values for quite some time. P.S. To use (and to see the output in the Xen ring buffer) one has to build the hypervisor with 'debug=y'. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [v1: ifdef xen_cpuid_base as it is X86 specific]
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2d1d3f3a |
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29-Aug-2013 |
Joe Perches <joe@perches.com> |
hvc_xen: Remove unnecessary __GFP_ZERO from kzalloc kzalloc already adds this __GFP_ZERO. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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23b7eaf8 |
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29-Aug-2013 |
Joe Perches <joe@perches.com> |
hvc_xen: Remove unnecessary __GFP_ZERO from kzalloc kzalloc already adds this __GFP_ZERO. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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3216dceb |
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19-Feb-2013 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
xen: introduce xen_remap, use it instead of ioremap ioremap can't be used to map ring pages on ARM because it uses device memory caching attributes (MT_DEVICE*). Introduce a Xen specific abstraction to map ring pages, called xen_remap, that is defined as ioremap on x86 (no behavioral changes). On ARM it explicitly calls __arm_ioremap with the right caching attributes: MT_MEMORY. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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9671f099 |
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19-Nov-2012 |
Bill Pemberton <wfp5p@virginia.edu> |
tty: remove use of __devinit CONFIG_HOTPLUG is going away as an option so __devinit is no longer needed. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Cc: Jiri Slaby <jirislaby@gmail.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Lucas Tavares <lucaskt@linux.vnet.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Peter Korsgaard <jacmet@sunsite.dk> Cc: Tony Prisk <linux@prisktech.co.nz> Acked-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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9b6934a3 |
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21-Sep-2012 |
David Vrabel <david.vrabel@citrix.com> |
xen/hvc: handle backend CLOSED without CLOSING Backend drivers shouldn't transistion to CLOSED unless the frontend is CLOSED. If a backend does transition to CLOSED too soon then the frontend may not see the CLOSING state and will not properly shutdown. So, treat an unexpected backend CLOSED state the same as CLOSING. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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4d9310e3 |
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06-Aug-2012 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
xen: missing includes Changes in v2: - remove pvclock hack; - remove include linux/types.h from xen/interface/xen.h. v3: - Compile under IA64 Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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37a80bf5 |
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26-Jun-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/hvc: Fix up checks when the info is allocated. Coverity would complain about this - even thought it looks OK. CID 401957 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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5842f576 |
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22-May-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/hvc: Check HVM_PARAM_CONSOLE_[EVTCHN|PFN] for correctness. We need to make sure that those parameters are setup to be correct. As such the value of 0 is deemed invalid and we find that we bail out. The hypervisor sets by default all of them to be zero and when the hypercall is done does a simple: a.value = d->arch.hvm_domain.params[a.index]; Which means that if the Xen toolstack forgot to setup the proper HVM_PARAM_CONSOLE_EVTCHN (or the PFN one), we would get the default value of 0 and use that. CC: stable@kernel.org Fixes-Oracle-Bug: 14091238 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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a32c88b9 |
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22-May-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/hvc: Fix error cases around HVM_PARAM_CONSOLE_PFN We weren't resetting the parameter to be passed in to a known default. Nor were we checking the return value of hvm_get_parameter. CC: stable@kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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2e5ad6b9 |
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22-May-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/hvc: Collapse error logic. All of the error paths are doing the same logic. In which case we might as well collapse them in one path. CC: stable@kernel.org Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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201a52be |
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15-May-2012 |
Dan Carpenter <dan.carpenter@oracle.com> |
hvc_xen: NULL dereference on allocation failure If kzalloc() returns a NULL here, we pass a NULL to xencons_disconnect_backend() which will cause an Oops. Also I removed the __GFP_ZERO while I was at it since kzalloc() implies __GFP_ZERO. CC: stable@kernel.org Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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bdb595b4 |
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15-May-2012 |
Dan Carpenter <dan.carpenter@oracle.com> |
tty: hvc_xen: NULL dereference on allocation failure If kzalloc() returns a NULL here, we pass a NULL to xencons_disconnect_backend() which will cause an Oops. Also I removed the __GFP_ZERO while I was at it since kzalloc() implies __GFP_ZERO. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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cf8e019b |
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21-Feb-2012 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
hvc_xen: introduce HVC_XEN_FRONTEND Introduce a new config option HVC_XEN_FRONTEND to enable/disable the xenbus based pv console frontend. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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30-Jan-2012 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
hvc_xen: implement multiconsole support This patch implements support for multiple consoles: consoles other than the first one are setup using the traditional xenbus and grant-table based mechanism. We use a list to keep track of the allocated consoles, we don't expect too many of them anyway. Changes in v3: - call hvc_remove before removing the console from xenconsoles; - do not lock xencons_lock twice in the destruction path; - use the DEFINE_XENBUS_DRIVER macro. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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eb5ef071 |
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27-Jan-2012 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
hvc_xen: support PV on HVM consoles Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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d4e33fac |
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26-Jan-2012 |
Alan Cox <alan@linux.intel.com> |
serial: Kill off NO_IRQ We transform the offenders into a test of irq <= 0 which will be ok while the ARM people get their platform sorted. Once that is done (or in a while if they don't do it anyway) then we will change them all to !irq checks. For arch specific drivers that are already using NO_IRQ = 0 we just test against zero so we don't need to re-review them later. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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dced35ae |
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28-Mar-2011 |
Thomas Gleixner <tglx@linutronix.de> |
drivers: Final irq namespace conversion Scripted with coccinelle. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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bbd5a762 |
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07-Mar-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/hvc: Disable probe_irq_on/off from poking the hvc-console IRQ line. This fixes a particular nasty racing problem found when using Xen hypervisor with the console (hvc) output being routed to the serial port and the serial port receiving data when probe_irq_off(probe_irq_on) is running. Specifically the bug manifests itself with: [ 4.470693] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 4.470693] IP: [<ffffffff810a8c65>] handle_IRQ_event+0xe/0xc9 ..snip.. [ 4.470693] Call Trace: [ 4.470693] <IRQ> [ 4.470693] [<ffffffff810aa645>] handle_percpu_irq+0x3c/0x69 [ 4.470693] [<ffffffff8123cda7>] __xen_evtchn_do_upcall+0xfd/0x195 [ 4.470693] [<ffffffff810308cf>] ? xen_restore_fl_direct_end+0x0/0x1 [ 4.470693] [<ffffffff8123d873>] xen_evtchn_do_upcall+0x32/0x47 [ 4.470693] [<ffffffff81034dfe>] xen_do_hypervisor_callback+0x1e/0x30 [ 4.470693] <EOI> [ 4.470693] [<ffffffff8100922a>] ? hypercall_page+0x22a/0x1000 [ 4.470693] [<ffffffff8100922a>] ? hypercall_page+0x22a/0x1000 [ 4.470693] [<ffffffff810301c5>] ? xen_force_evtchn_callback+0xd/0xf [ 4.470693] [<ffffffff810308e2>] ? check_events+0x12/0x20 [ 4.470693] [<ffffffff81030889>] ? xen_irq_enable_direct_end+0x0/0x7 [ 4.470693] [<ffffffff810ab0a0>] ? probe_irq_on+0x8f/0x1d7 [ 4.470693] [<ffffffff812b105e>] ? serial8250_config_port+0x7b7/0x9e6 [ 4.470693] [<ffffffff812ad66c>] ? uart_add_one_port+0x11b/0x305 The bug is trigged by three actors working together: A). serial_8250_config_port calling probe_irq_off(probe_irq_on()) wherein all of the IRQ handlers are being started and shut off. The functions utilize the sleep functions so the minimum time they are run is 120 msec. B). Xen hypervisor receiving on the serial line any character and setting the bits in the event channel - during this 120 msec timeframe. C). The hvc API makes a call to 'request_irq' (and hence setting desc->action to a valid value), much much later - when user space opens /dev/console (hvc_open). To make the console usable during bootup, the Xen HVC implementation sets the IRQ chip (and correspondingly the event channel) much earlier. The IRQ chip handler that is used is the handle_percpu_irq (aaca49642b92c8a57d3ca5029a5a94019c7af69f) Back to the issue. When A) is being called it ends up calling the xen_percpu_chip's chip->startup twice and chip->shutdown once. Those are set to the default_startup and mask_irq (events.c) respectivly. If (and this seems to depend on what serial concentrator you use), B) gets data from the serial port it sets in the event channel a pending bit. When A) calls chip->startup(), the masking of the pending bit, and unmasking of the event channel mask, and also setting of the upcall_pending flag is done (since there is data present on the event channel). If before the 120 msec has elapsed, any IRQ handler (Xen IRQ has one IRQ handler, which checks the event channels bitmap to figure which one to call) is called we end up calling the handle_percpu_irq. The handle_percpu_irq calls desc->action (which is NULL) and we blow up. Caveats: I could only reproduce this on 2.6.32 pvops. I am not sure why this is not showing up on 2.6.38 kernel. The probe_irq_on/off has code to disable poking specific IRQ lines. This is done by using the set_irq_noprobe() and then we do not have to worry about the handle_percpu_irq being called before the IRQ action handler has been installed. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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728674a7 |
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13-Jan-2011 |
Greg Kroah-Hartman <gregkh@suse.de> |
tty: move hvc drivers to drivers/tty/hvc/ As requested by Arnd Bergmann, the hvc drivers are now moved to the drivers/tty/hvc/ directory. The virtio_console.c driver was also moved, as it required the hvc_console.h file to be able to be built, and it really is a hvc driver. Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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