linux/drivers/char, branch v5.17

virtio_console: break out of buf poll on remove

2022-03-04T13:33:22Z

A common pattern for device reset is currently: vdev->config->reset(vdev); .. cleanup .. reset prevents new interrupts from arriving and waits for interrupt handlers to finish. However if - as is common - the handler queues a work request which is flushed during the cleanup stage, we have code adding buffers / trying to get buffers while device is reset. Not good. This was reproduced by running modprobe virtio_console modprobe -r virtio_console in a loop. Fix this up by calling virtio_break_device + flush before reset. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1786239 Signed-off-by: Michael S. Tsirkin

random: only call crng_finalize_init() for primary_crng

2022-02-04T18:22:32Z

crng_finalize_init() returns instantly if it is called for another pool than primary_crng. The test whether crng_finalize_init() is still required can be moved to the relevant caller in crng_reseed(), and crng_need_final_init can be reset to false if crng_finalize_init() is called with workqueues ready. Then, no previous callsite will call crng_finalize_init() unless it is needed, and we can get rid of the superfluous function parameter. Signed-off-by: Dominik Brodowski Signed-off-by: Jason A. Donenfeld

random: access primary_pool directly rather than through pointer

2022-02-04T18:22:32Z

Both crng_initialize_primary() and crng_init_try_arch_early() are only called for the primary_pool. Accessing it directly instead of through a function parameter simplifies the code. Signed-off-by: Dominik Brodowski Signed-off-by: Jason A. Donenfeld

random: wake up /dev/random writers after zap

2022-02-04T18:22:32Z

When account() is called, and the amount of entropy dips below random_write_wakeup_bits, we wake up the random writers, so that they can write some more in. However, the RNDZAPENTCNT/RNDCLEARPOOL ioctl sets the entropy count to zero -- a potential reduction just like account() -- but does not unblock writers. This commit adds the missing logic to that ioctl to unblock waiting writers. Reviewed-by: Dominik Brodowski Signed-off-by: Jason A. Donenfeld

random: continually use hwgenerator randomness

2022-02-04T18:22:32Z

The rngd kernel thread may sleep indefinitely if the entropy count is kept above random_write_wakeup_bits by other entropy sources. To make best use of multiple sources of randomness, mix entropy from hardware RNGs into the pool at least once within CRNG_RESEED_INTERVAL. Cc: Herbert Xu Cc: Jason A. Donenfeld Signed-off-by: Dominik Brodowski Signed-off-by: Jason A. Donenfeld

random: move the random sysctl declarations to its own file

2022-01-22T06:33:35Z

kernel/sysctl.c is a kitchen sink where everyone leaves their dirty dishes, this makes it very difficult to maintain. To help with this maintenance let's start by moving sysctls to places where they actually belong. The proc sysctl maintainers do not want to know what sysctl knobs you wish to add for your own piece of code, we just care about the core logic. So move the random sysctls to their own file and use register_sysctl_init(). [mcgrof@kernel.org: commit log update to justify the move] Link: https://lkml.kernel.org/r/20211124231435.1445213-3-mcgrof@kernel.org Signed-off-by: Xiaoming Ni Signed-off-by: Luis Chamberlain Cc: Al Viro Cc: Amir Goldstein Cc: Andy Shevchenko Cc: Antti Palosaari Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Benjamin LaHaise Cc: Clemens Ladisch Cc: David Airlie Cc: Douglas Gilbert Cc: Eric Biederman Cc: Greg Kroah-Hartman Cc: Iurii Zaikin Cc: James E.J. Bottomley Cc: Jani Nikula Cc: Jani Nikula Cc: Jan Kara Cc: Joel Becker Cc: John Ogness Cc: Joonas Lahtinen Cc: Joseph Qi Cc: Julia Lawall Cc: Kees Cook Cc: Lukas Middendorf Cc: Mark Fasheh Cc: Martin K. Petersen Cc: Paul Turner Cc: Peter Zijlstra Cc: Petr Mladek Cc: Phillip Potter Cc: Qing Wang Cc: "Rafael J. Wysocki" Cc: Rodrigo Vivi Cc: Sebastian Reichel Cc: Sergey Senozhatsky Cc: Stephen Kitt Cc: Steven Rostedt (VMware) Cc: Suren Baghdasaryan Cc: Tetsuo Handa Cc: "Theodore Ts'o" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

hpet: simplify subdirectory registration with register_sysctl()

2022-01-22T06:33:34Z

Patch series "sysctl: second set of kernel/sysctl cleanups", v2. This is the 2nd set of kernel/sysctl.c cleanups. The diff stat should reflect how this is a much better way to deal with theses. Fortunately coccinelle can be used to ensure correctness for most of these and/or future merge conflicts. Note that since this is part of a larger effort to cleanup kernel/sysctl.c I think we have no other option but to go with merging these patches in either Andrew's tree or keep them staged in a separate tree and send a merge request later. Otherwise kernel/sysctl.c will end up becoming a sore spot for the next merge window. This patch (of 8): There is no need to user boiler plate code to specify a set of base directories we're going to stuff sysctls under. Simplify this by using register_sysctl() and specifying the directory path directly. // pycocci sysctl-subdir-register-sysctl-simplify.cocci drivers/char/hpet.c @c1@ expression E1; identifier subdir, sysctls; @@ static struct ctl_table subdir[] = { { .procname = E1, .maxlen = 0, .mode = 0555, .child = sysctls, }, { } }; @c2@ identifier c1.subdir; expression E2; identifier base; @@ static struct ctl_table base[] = { { .procname = E2, .maxlen = 0, .mode = 0555, .child = subdir, }, { } }; @c3@ identifier c2.base; identifier header; @@ header = register_sysctl_table(base); @r1 depends on c1 && c2 && c3@ expression c1.E1; identifier c1.subdir, c1.sysctls; @@ -static struct ctl_table subdir[] = { - { - .procname = E1, - .maxlen = 0, - .mode = 0555, - .child = sysctls, - }, - { } -}; @r2 depends on c1 && c2 && c3@ identifier c1.subdir; expression c2.E2; identifier c2.base; @@ -static struct ctl_table base[] = { - { - .procname = E2, - .maxlen = 0, - .mode = 0555, - .child = subdir, - }, - { } -}; @initialize:python@ @@ def make_my_fresh_expression(s1, s2): return '"' + s1.strip('"') + "/" + s2.strip('"') + '"' @r3 depends on c1 && c2 && c3@ expression c1.E1; identifier c1.sysctls; expression c2.E2; identifier c2.base; identifier c3.header; fresh identifier E3 = script:python(E2, E1) { make_my_fresh_expression(E2, E1) }; @@ header = -register_sysctl_table(base); +register_sysctl(E3, sysctls); Generated-by: Coccinelle SmPL Link: https://lkml.kernel.org/r/20211123202422.819032-1-mcgrof@kernel.org Link: https://lkml.kernel.org/r/20211123202422.819032-2-mcgrof@kernel.org Signed-off-by: Luis Chamberlain Cc: Kees Cook Cc: Iurii Zaikin Cc: Xiaoming Ni Cc: "Eric W. Biederman" Cc: Clemens Ladisch Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Cc: Jani Nikula Cc: Joonas Lahtinen Cc: Rodrigo Vivi Cc: David Airlie Cc: Benjamin Herrenschmidt Cc: Mark Fasheh Cc: Joel Becker Cc: Joseph Qi Cc: Jan Kara Cc: Amir Goldstein Cc: Phillip Potter Cc: Al Viro Cc: Julia Lawall Cc: Lukas Middendorf Cc: Antti Palosaari Cc: Andy Shevchenko Cc: Benjamin LaHaise Cc: Paul Turner Cc: Peter Zijlstra Cc: Petr Mladek Cc: Qing Wang Cc: Sebastian Reichel Cc: Sergey Senozhatsky Cc: Stephen Kitt Cc: Tetsuo Handa Cc: Douglas Gilbert Cc: James E.J. Bottomley Cc: Jani Nikula Cc: John Ogness Cc: Martin K. Petersen Cc: "Rafael J. Wysocki" Cc: Steven Rostedt (VMware) Cc: Suren Baghdasaryan Cc: "Theodore Ts'o" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

random: simplify arithmetic function flow in account()

2022-01-18T12:03:56Z

Now that have_bytes is never modified, we can simplify this function. First, we move the check for negative entropy_count to be first. That ensures that subsequent reads of this will be non-negative. Then, have_bytes and ibytes can be folded into their one use site in the min_t() function. Suggested-by: Dominik Brodowski Reviewed-by: Dominik Brodowski Signed-off-by: Jason A. Donenfeld

random: selectively clang-format where it makes sense

2022-01-18T12:03:56Z

This is an old driver that has seen a lot of different eras of kernel coding style. In an effort to make it easier to code for, unify the coding style around the current norm, by accepting some of -- but certainly not all of -- the suggestions from clang-format. This should remove ambiguity in coding style, especially with regards to spacing, when code is being changed or amended. Consequently it also makes code review easier on the eyes, following one uniform style rather than several. Reviewed-by: Dominik Brodowski Signed-off-by: Jason A. Donenfeld

random: access input_pool_data directly rather than through pointer

2022-01-18T12:03:56Z

This gets rid of another abstraction we no longer need. It would be nice if we could instead make pool an array rather than a pointer, but the latent entropy plugin won't be able to do its magic in that case. So instead we put all accesses to the input pool's actual data through the input_pool_data array directly. Reviewed-by: Dominik Brodowski Signed-off-by: Jason A. Donenfeld