linux-dev/drivers/firmware/google, branch master

firmware: google: Test spinlock on panic path to avoid lockups

2022-09-24T12:59:44Z

Currently the gsmi driver registers a panic notifier as well as reboot and die notifiers. The callbacks registered are called in atomic and very limited context - for instance, panic disables preemption and local IRQs, also all secondary CPUs (not executing the panic path) are shutdown. With that said, taking a spinlock in this scenario is a dangerous invitation for lockup scenarios. So, fix that by checking if the spinlock is free to acquire in the panic notifier callback - if not, bail-out and avoid a potential hang. Fixes: 74c5b31c6618 ("driver: Google EFI SMI") Cc: Andrew Morton Cc: Ard Biesheuvel Cc: David Gow Cc: Greg Kroah-Hartman Cc: Julius Werner Cc: Petr Mladek Reviewed-by: Evan Green Signed-off-by: Guilherme G. Piccoli Link: https://lore.kernel.org/r/20220909200755.189679-1-gpiccoli@igalia.com Signed-off-by: Greg Kroah-Hartman

firmware: google: Properly state IOMEM dependency

2022-03-18T13:18:15Z

The Google Coreboot implementation requires IOMEM functions (memmremap, memunmap, devm_memremap), but does not specify this is its Kconfig. This results in build errors when HAS_IOMEM is not set, such as on some UML configurations: /usr/bin/ld: drivers/firmware/google/coreboot_table.o: in function `coreboot_table_probe': coreboot_table.c:(.text+0x311): undefined reference to `memremap' /usr/bin/ld: coreboot_table.c:(.text+0x34e): undefined reference to `memunmap' /usr/bin/ld: drivers/firmware/google/memconsole-coreboot.o: in function `memconsole_probe': memconsole-coreboot.c:(.text+0x12d): undefined reference to `memremap' /usr/bin/ld: memconsole-coreboot.c:(.text+0x17e): undefined reference to `devm_memremap' /usr/bin/ld: memconsole-coreboot.c:(.text+0x191): undefined reference to `memunmap' /usr/bin/ld: drivers/firmware/google/vpd.o: in function `vpd_section_destroy.isra.0': vpd.c:(.text+0x300): undefined reference to `memunmap' /usr/bin/ld: drivers/firmware/google/vpd.o: in function `vpd_section_init': vpd.c:(.text+0x382): undefined reference to `memremap' /usr/bin/ld: vpd.c:(.text+0x459): undefined reference to `memunmap' /usr/bin/ld: drivers/firmware/google/vpd.o: in function `vpd_probe': vpd.c:(.text+0x59d): undefined reference to `memremap' /usr/bin/ld: vpd.c:(.text+0x5d3): undefined reference to `memunmap' collect2: error: ld returned 1 exit status Fixes: a28aad66da8b ("firmware: coreboot: Collapse platform drivers into bus core") Acked-By: anton ivanov Acked-By: Julius Werner Signed-off-by: David Gow Link: https://lore.kernel.org/r/20220225041502.1901806-1-davidgow@google.com Signed-off-by: Greg Kroah-Hartman

firmware: Update Kconfig help text for Google firmware

2021-12-21T09:12:31Z

The help text for GOOGLE_FIRMWARE states that it should only be enabled when building a kernel for Google's own servers. However, many of the drivers dependent on it are also useful on Chromebooks or on any platform using coreboot. Update the help text to reflect this double duty. Fixes: d384d6f43d1e ("firmware: google memconsole: Add coreboot support") Reviewed-by: Julius Werner Signed-off-by: Ben Hutchings Link: https://lore.kernel.org/r/20180618225540.GD14131@decadent.org.uk Signed-off-by: Greg Kroah-Hartman

bus: Make remove callback return void

2021-07-21T09:53:42Z

The driver core ignores the return value of this callback because there is only little it can do when a device disappears. This is the final bit of a long lasting cleanup quest where several buses were converted to also return void from their remove callback. Additionally some resource leaks were fixed that were caused by drivers returning an error code in the expectation that the driver won't go away. With struct bus_type::remove returning void it's prevented that newly implemented buses return an ignored error code and so don't anticipate wrong expectations for driver authors. Reviewed-by: Tom Rix (For fpga) Reviewed-by: Mathieu Poirier Reviewed-by: Cornelia Huck (For drivers/s390 and drivers/vfio) Acked-by: Russell King (Oracle) (For ARM, Amba and related parts) Acked-by: Mark Brown Acked-by: Chen-Yu Tsai (for sunxi-rsb) Acked-by: Pali Rohár Acked-by: Mauro Carvalho Chehab (for media) Acked-by: Hans de Goede (For drivers/platform) Acked-by: Alexandre Belloni Acked-By: Vinod Koul Acked-by: Juergen Gross (For xen) Acked-by: Lee Jones (For mfd) Acked-by: Johannes Thumshirn (For mcb) Acked-by: Johan Hovold Acked-by: Srinivas Kandagatla (For slimbus) Acked-by: Kirti Wankhede (For vfio) Acked-by: Maximilian Luz Acked-by: Heikki Krogerus (For ulpi and typec) Acked-by: Samuel Iglesias Gonsálvez (For ipack) Acked-by: Geoff Levand (For ps3) Acked-by: Yehezkel Bernat (For thunderbolt) Acked-by: Alexander Shishkin (For intel_th) Acked-by: Dominik Brodowski (For pcmcia) Acked-by: Rafael J. Wysocki (For ACPI) Acked-by: Bjorn Andersson (rpmsg and apr) Acked-by: Srinivas Pandruvada (For intel-ish-hid) Acked-by: Dan Williams (For CXL, DAX, and NVDIMM) Acked-by: William Breathitt Gray (For isa) Acked-by: Stefan Richter (For firewire) Acked-by: Benjamin Tissoires (For hid) Acked-by: Thorsten Scherer (For siox) Acked-by: Sven Van Asbroeck (For anybuss) Acked-by: Ulf Hansson (For MMC) Acked-by: Wolfram Sang # for I2C Acked-by: Sudeep Holla Acked-by: Geert Uytterhoeven Acked-by: Dmitry Torokhov Acked-by: Finn Thain Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman

kernel.h: split out panic and oops helpers

2021-07-01T18:06:04Z

kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt to start cleaning it up by splitting out panic and oops helpers. There are several purposes of doing this: - dropping dependency in bug.h - dropping a loop by moving out panic_notifier.h - unload kernel.h from something which has its own domain At the same time convert users tree-wide to use new headers, although for the time being include new header back to kernel.h to avoid twisted indirected includes for existing users. [akpm@linux-foundation.org: thread_info.h needs limits.h] [andriy.shevchenko@linux.intel.com: ia64 fix] Link: https://lkml.kernel.org/r/20210520130557.55277-1-andriy.shevchenko@linux.intel.com Link: https://lkml.kernel.org/r/20210511074137.33666-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko Reviewed-by: Bjorn Andersson Co-developed-by: Andrew Morton Acked-by: Mike Rapoport Acked-by: Corey Minyard Acked-by: Christian Brauner Acked-by: Arnd Bergmann Acked-by: Kees Cook Acked-by: Wei Liu Acked-by: Rasmus Villemoes Signed-off-by: Andrew Morton Acked-by: Sebastian Reichel Acked-by: Luis Chamberlain Acked-by: Stephen Boyd Acked-by: Thomas Bogendoerfer Acked-by: Helge Deller # parisc Signed-off-by: Linus Torvalds

firmware: google: Enable s0ix logging by default

2021-04-02T14:30:21Z

Many moons ago, support was added to the SMI handlers to log s0ix entry and exit. Early iterations of firmware on Apollo Lake correctly returned "unsupported" for this new command they did not recognize, but unfortunately also contained a quirk where this command would cause them to power down rather than resume from s0ix. Fixes for this quirk were pushed out long ago, so all APL devices still in the field should have updated firmware. As such, we no longer need to have the s0ix_logging_enable be opt-in, where every new platform has to add this to their kernel commandline parameters. Change it to be on by default. In theory we could remove the parameter altogether: updated versions of Chrome OS containing a kernel with this change would also be coupled with firmware that behaves properly with these commands. Eventually we should probably do that. For now, convert this to an opt-out parameter so there's an emergency valve for people who are deliberately running old firmware, or as an escape hatch in case of unforeseen regressions. Signed-off-by: Evan Green Link: https://lore.kernel.org/r/20210401140430.1.Ie141e6044d9b0d5aba72cb08857fdb43660c54d3@changeid Signed-off-by: Greg Kroah-Hartman

firmware: google: make coreboot driver's remove callback return void

2021-02-09T11:12:43Z

All coreboot drivers return 0 unconditionally in their remove callback. Also the device core ignores the return value of the struct bus_type::remove(), so make the coreboot remove callback return void instead of giving driver authors the illusion they could return an error code here. All drivers are adapted accordingly. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20210126215339.706021-1-uwe@kleine-koenig.org Signed-off-by: Greg Kroah-Hartman

firmware: gsmi: Drop the use of dma_pool_* API functions

2020-11-09T17:48:06Z

GSMI driver uses dma_pool_* API functions for buffer allocation because it requires that the SMI buffers are allocated within 32-bit physical address space. However, this does not work well with IOMMU since there is no real device and hence no domain associated with the device. Since this is not a real device, it does not require any device address(IOVA) for the buffer allocations. The only requirement is to ensure that the physical address allocated to the buffer is within 32-bit physical address space. This is because the buffers have nothing to do with DMA at all. It is required for communication with firmware executing in SMI mode which has access only to the bottom 4GiB of memory. Hence, this change switches to using a SLAB cache created with SLAB_CACHE_DMA32 that guarantees that the allocation happens from the DMA32 memory zone. All calls to dma_pool_* are replaced with kmem_cache_*. In addition to that, all the code for managing the dma_pool for GSMI platform device is dropped. Signed-off-by: Furquan Shaikh Reviewed-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20201022071550.1192947-1-furquan@google.com Signed-off-by: Greg Kroah-Hartman

efi: gsmi: fix false dependency on CONFIG_EFI_VARS

2020-09-29T17:40:57Z

The gsmi code does not actually rely on CONFIG_EFI_VARS, since it only uses the efivars abstraction that is included unconditionally when CONFIG_EFI is defined. CONFIG_EFI_VARS controls the inclusion of the code that exposes the sysfs entries, and which has been deprecated for some time. Signed-off-by: Ard Biesheuvel

firmware: google: vpd: Replace zero-length array with flexible-array member

2020-06-16T04:08:21Z

There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://github.com/KSPP/linux/issues/21 Signed-off-by: Gustavo A. R. Silva