linux-dev/drivers/char/hw_random, branch master

hwrng: bcm2835 - use hwrng_msleep() instead of cpu_relax()

2022-10-14T11:03:09Z

Rather than busy looping, yield back to the scheduler and sleep for a bit in the event that there's no data. This should hopefully prevent the stalls that Mark reported: <6>[ 3.362859] Freeing initrd memory: 16196K <3>[ 23.160131] rcu: INFO: rcu_sched self-detected stall on CPU <3>[ 23.166057] rcu: 0-....: (2099 ticks this GP) idle=03b4/1/0x40000002 softirq=28/28 fqs=1050 <4>[ 23.174895] (t=2101 jiffies g=-1147 q=2353 ncpus=4) <4>[ 23.180203] CPU: 0 PID: 49 Comm: hwrng Not tainted 6.0.0 #1 <4>[ 23.186125] Hardware name: BCM2835 <4>[ 23.189837] PC is at bcm2835_rng_read+0x30/0x6c <4>[ 23.194709] LR is at hwrng_fillfn+0x71/0xf4 <4>[ 23.199218] pc : [] lr : [] psr: 40000033 <4>[ 23.205840] sp : f093df70 ip : 00000000 fp : 00000000 <4>[ 23.211404] r10: c3c7e800 r9 : 00000000 r8 : c17e6b20 <4>[ 23.216968] r7 : c17e6b64 r6 : c18b0a74 r5 : c07ccd99 r4 : c3f171c0 <4>[ 23.223855] r3 : 000fffff r2 : 00000040 r1 : c3c7e800 r0 : c3f171c0 <4>[ 23.230743] Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA Thumb Segment none <4>[ 23.238426] Control: 50c5387d Table: 0020406a DAC: 00000051 <4>[ 23.244519] CPU: 0 PID: 49 Comm: hwrng Not tainted 6.0.0 #1 Link: https://lore.kernel.org/all/Y0QJLauamRnCDUef@sirena.org.uk/ Signed-off-by: Jason A. Donenfeld Acked-by: Florian Fainelli Signed-off-by: Herbert Xu

hwrng: core - start hwrng kthread also for untrusted sources

2022-09-30T05:59:12Z

Start the hwrng kthread even if the hwrng source has a quality setting of zero. Then, every crng reseed interval, one batch of data from this zero-quality hwrng source will be mixed into the CRNG pool. This patch is based on the assumption that data from a hwrng source will not actively harm the CRNG state. Instead, many hwrng sources (such as TPM devices), even though they are assigend a quality level of zero, actually provide some entropy, which is good enough to mix into the CRNG pool every once in a while. Cc: Herbert Xu Cc: Jason A. Donenfeld Signed-off-by: Dominik Brodowski Signed-off-by: Herbert Xu

hwrng: imx-rngc - Moving IRQ handler registering after imx_rngc_irq_mask_clear()

2022-09-02T10:37:23Z

Issue: While servicing interrupt, if the IRQ happens to be because of a SEED_DONE due to a previous boot stage, you end up completing the completion prematurely, hence causing kernel to crash while booting. Fix: Moving IRQ handler registering after imx_rngc_irq_mask_clear() Fixes: 1d5449445bd0 (hwrng: mx-rngc - add a driver for Freescale RNGC) Signed-off-by: Kshitiz Varshney Signed-off-by: Herbert Xu

hwrng: imx-rngc - use devres for hwrng registration

2022-08-26T10:49:10Z

Replace hwrng_register with devm_hwrng_register and let devres unregister our hwrng when the device is removed. It's possible to do this now that devres also handles clock disable+uprepare. When we had to disable+unprepare the clock ourselves, we had to unregister the hwrng before this and couldn't use devres. There's nothing left to do for imx_rngc_remove, this function can go. Signed-off-by: Martin Kaiser Signed-off-by: Herbert Xu

hwrng: imx-rngc - use devm_clk_get_enabled

2022-08-26T10:49:10Z

Use the new devm_clk_get_enabled function to get our clock. We don't have to disable and unprepare the clock ourselves any more in error paths and in the remove function. Signed-off-by: Martin Kaiser Signed-off-by: Herbert Xu

hwrng: imx-rngc - use KBUILD_MODNAME as driver name

2022-08-19T10:39:39Z

Use KBUILD_MODNAME instead of hard coding the driver name. Signed-off-by: Martin Kaiser Signed-off-by: Herbert Xu

hwrng: arm-smccc-trng - fix NO_ENTROPY handling

2022-08-19T10:39:35Z

The SMCCC_RET_TRNG_NO_ENTROPY switch arm is never used because the NO_ENTROPY return value is negative and negative values are handled above the switch by immediately returning. Fix by handling errors using a default arm in the switch. Fixes: 0888d04b47a1 ("hwrng: Add Arm SMCCC TRNG based driver") Signed-off-by: James Cowgill Signed-off-by: Herbert Xu

hwrng: core - let sleep be interrupted when unregistering hwrng

2022-08-19T10:39:34Z

There are two deadlock scenarios that need addressing, which cause problems when the computer goes to sleep, the interface is set down, and hwrng_unregister() is called. When the deadlock is hit, sleep is delayed for tens of seconds, causing it to fail. These scenarios are: 1) The hwrng kthread can't be stopped while it's sleeping, because it uses msleep_interruptible() which does not react to kthread_stop. 2) A normal user thread can't be interrupted by hwrng_unregister() while it's sleeping, because hwrng_unregister() is called from elsewhere. We solve both issues by add a completion object called dying that fulfils waiters once we have started the process in hwrng_unregister. At the same time, we should cleanup a common and useless dmesg splat in the same area. Cc: Reported-by: Gregory Erwin Fixes: fcd09c90c3c5 ("ath9k: use hw_random API instead of directly dumping into random.c") Link: https://lore.kernel.org/all/CAO+Okf6ZJC5-nTE_EJUGQtd8JiCkiEHytGgDsFGTEjs0c00giw@mail.gmail.com/ Link: https://lore.kernel.org/lkml/CAO+Okf5k+C+SE6pMVfPf-d8MfVPVq4PO7EY8Hys_DVXtent3HA@mail.gmail.com/ Link: https://bugs.archlinux.org/task/75138 Signed-off-by: Jason A. Donenfeld Signed-off-by: Herbert Xu Acked-by: Toke Høiland-Jørgensen Acked-by: Kalle Valo Signed-off-by: Herbert Xu

Merge tag 's390-5.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2022-08-07T00:05:21Z

Pull s390 updates from Alexander Gordeev: - Rework copy_oldmem_page() callback to take an iov_iter. This includes a few prerequisite updates and fixes to the oldmem reading code. - Rework cpufeature implementation to allow for various CPU feature indications, which is not only limited to hardware capabilities, but also allows CPU facilities. - Use the cpufeature rework to autoload Ultravisor module when CPU facility 158 is available. - Add ELF note type for encrypted CPU state of a protected virtual CPU. The zgetdump tool from s390-tools package will decrypt the CPU state using a Customer Communication Key and overwrite respective notes to make the data accessible for crash and other debugging tools. - Use vzalloc() instead of vmalloc() + memset() in ChaCha20 crypto test. - Fix incorrect recovery of kretprobe modified return address in stacktrace. - Switch the NMI handler to use generic irqentry_nmi_enter() and irqentry_nmi_exit() helper functions. - Rework the cryptographic Adjunct Processors (AP) pass-through design to support dynamic changes to the AP matrix of a running guest as well as to implement more of the AP architecture. - Minor boot code cleanups. - Grammar and typo fixes to hmcdrv and tape drivers. * tag 's390-5.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (46 commits) Revert "s390/smp: enforce lowcore protection on CPU restart" Revert "s390/smp: rework absolute lowcore access" Revert "s390/smp,ptdump: add absolute lowcore markers" s390/unwind: fix fgraph return address recovery s390/nmi: use irqentry_nmi_enter()/irqentry_nmi_exit() s390: add ELF note type for encrypted CPU state of a PV VCPU s390/smp,ptdump: add absolute lowcore markers s390/smp: rework absolute lowcore access s390/setup: rearrange absolute lowcore initialization s390/boot: cleanup adjust_to_uv_max() function s390/smp: enforce lowcore protection on CPU restart s390/tape: fix comment typo s390/hmcdrv: fix Kconfig "its" grammar s390/docs: fix warnings for vfio_ap driver doc s390/docs: fix warnings for vfio_ap driver lock usage doc s390/crash: support multi-segment iterators s390/crash: use static swap buffer for copy_to_user_real() s390/crash: move copy_to_user_real() to crash_dump.c s390/zcore: fix race when reading from hardware system area s390/crash: fix incorrect number of bytes to copy to user space ...

Merge tag 'powerpc-6.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2022-08-06T23:38:17Z

Pull powerpc updates from Michael Ellerman: - Add support for syscall stack randomization - Add support for atomic operations to the 32 & 64-bit BPF JIT - Full support for KASAN on 64-bit Book3E - Add a watchdog driver for the new PowerVM hypervisor watchdog - Add a number of new selftests for the Power10 PMU support - Add a driver for the PowerVM Platform KeyStore - Increase the NMI watchdog timeout during live partition migration, to avoid timeouts due to increased memory access latency - Add support for using the 'linux,pci-domain' device tree property for PCI domain assignment - Many other small features and fixes Thanks to Alexey Kardashevskiy, Andy Shevchenko, Arnd Bergmann, Athira Rajeev, Bagas Sanjaya, Christophe Leroy, Erhard Furtner, Fabiano Rosas, Greg Kroah-Hartman, Greg Kurz, Haowen Bai, Hari Bathini, Jason A. Donenfeld, Jason Wang, Jiang Jian, Joel Stanley, Juerg Haefliger, Kajol Jain, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Masahiro Yamada, Maxime Bizon, Miaoqian Lin, Murilo Opsfelder Araújo, Nathan Lynch, Naveen N. Rao, Nayna Jain, Nicholas Piggin, Ning Qiang, Pali Rohár, Petr Mladek, Rashmica Gupta, Sachin Sant, Scott Cheloha, Segher Boessenkool, Stephen Rothwell, Uwe Kleine-König, Wolfram Sang, Xiu Jianfeng, and Zhouyi Zhou. * tag 'powerpc-6.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (191 commits) powerpc/64e: Fix kexec build error EDAC/ppc_4xx: Include required of_irq header directly powerpc/pci: Fix PHB numbering when using opal-phbid powerpc/64: Init jump labels before parse_early_param() selftests/powerpc: Avoid GCC 12 uninitialised variable warning powerpc/cell/axon_msi: Fix refcount leak in setup_msi_msg_address powerpc/xive: Fix refcount leak in xive_get_max_prio powerpc/spufs: Fix refcount leak in spufs_init_isolated_loader powerpc/perf: Include caps feature for power10 DD1 version powerpc: add support for syscall stack randomization powerpc: Move system_call_exception() to syscall.c powerpc/powernv: rename remaining rng powernv_ functions to pnv_ powerpc/powernv/kvm: Use darn for H_RANDOM on Power9 powerpc/powernv: Avoid crashing if rng is NULL selftests/powerpc: Fix matrix multiply assist test powerpc/signal: Update comment for clarity powerpc: make facility_unavailable_exception 64s powerpc/platforms/83xx/suspend: Remove write-only global variable powerpc/platforms/83xx/suspend: Prevent unloading the driver powerpc/platforms/83xx/suspend: Reorder to get rid of a forward declaration ...