user/sven/linux.git/init, branch v5.6.13

printk: queue wake_up_klogd irq_work only if per-CPU areas are ready

2020-05-02T06:50:39Z

commit ab6f762f0f53162d41497708b33c9a3236d3609e upstream. printk_deferred(), similarly to printk_safe/printk_nmi, does not immediately attempt to print a new message on the consoles, avoiding calls into non-reentrant kernel paths, e.g. scheduler or timekeeping, which potentially can deadlock the system. Those printk() flavors, instead, rely on per-CPU flush irq_work to print messages from safer contexts. For same reasons (recursive scheduler or timekeeping calls) printk() uses per-CPU irq_work in order to wake up user space syslog/kmsg readers. However, only printk_safe/printk_nmi do make sure that per-CPU areas have been initialised and that it's safe to modify per-CPU irq_work. This means that, for instance, should printk_deferred() be invoked "too early", that is before per-CPU areas are initialised, printk_deferred() will perform illegal per-CPU access. Lech Perczak [0] reports that after commit 1b710b1b10ef ("char/random: silence a lockdep splat with printk()") user-space syslog/kmsg readers are not able to read new kernel messages. The reason is printk_deferred() being called too early (as was pointed out by Petr and John). Fix printk_deferred() and do not queue per-CPU irq_work before per-CPU areas are initialized. Link: https://lore.kernel.org/lkml/aa0732c6-5c4e-8a8b-a1c1-75ebe3dca05b@camlintechnologies.com/ Reported-by: Lech Perczak Signed-off-by: Sergey Senozhatsky Tested-by: Jann Horn Reviewed-by: Petr Mladek Cc: Greg Kroah-Hartman Cc: Theodore Ts'o Cc: John Ogness Signed-off-by: Linus Torvalds Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

int128: fix __uint128_t compiler test in Kconfig

2020-03-11T22:43:03Z

The support for __uint128_t is dependent on the target bit size. GCC that defaults to the 32-bit can still build the 64-bit kernel with -m64 flag passed. However, $(cc-option,-D__SIZEOF_INT128__=0) is evaluated against the default machine bit, which may not match to the kernel it is building. Theoretically, this could be evaluated separately for 64BIT/32BIT. config CC_HAS_INT128 bool default !$(cc-option,$(m64-flag) -D__SIZEOF_INT128__=0) if 64BIT default !$(cc-option,$(m32-flag) -D__SIZEOF_INT128__=0) I simplified it more because the 32-bit compiler is unlikely to support __uint128_t. Fixes: c12d3362a74b ("int128: move __uint128_t compiler test to Kconfig") Reported-by: George Spelvin Signed-off-by: Masahiro Yamada Tested-by: George Spelvin

Merge tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2020-02-26T18:34:42Z

Pull tracing and bootconfig updates: "Fixes and changes to bootconfig before it goes live in a release. Change in API of bootconfig (before it comes live in a release): - Have a magic value "BOOTCONFIG" in initrd to know a bootconfig exists - Set CONFIG_BOOT_CONFIG to 'n' by default - Show error if "bootconfig" on cmdline but not compiled in - Prevent redefining the same value - Have a way to append values - Added a SELECT BLK_DEV_INITRD to fix a build failure Synthetic event fixes: - Switch to raw_smp_processor_id() for recording CPU value in preempt section. (No care for what the value actually is) - Fix samples always recording u64 values - Fix endianess - Check number of values matches number of fields - Fix a printing bug Fix of trace_printk() breaking postponed start up tests Make a function static that is only used in a single file" * tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issue bootconfig: Add append value operator support bootconfig: Prohibit re-defining value on same key bootconfig: Print array as multiple commands for legacy command line bootconfig: Reject subkey and value on same parent key tools/bootconfig: Remove unneeded error message silencer bootconfig: Add bootconfig magic word for indicating bootconfig explicitly bootconfig: Set CONFIG_BOOT_CONFIG=n by default tracing: Clear trace_state when starting trace bootconfig: Mark boot_config_checksum() static tracing: Disable trace_printk() on post poned tests tracing: Have synthetic event test use raw_smp_processor_id() tracing: Fix number printing bug in print_synth_event() tracing: Check that number of vals matches number of synth event fields tracing: Make synth_event trace functions endian-correct tracing: Make sure synth_event_trace() example always uses u64

bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issue

2020-02-26T00:07:58Z

Since commit d8a953ddde5e ("bootconfig: Set CONFIG_BOOT_CONFIG=n by default") also changed the CONFIG_BOOTTIME_TRACING to select CONFIG_BOOT_CONFIG to show the boot-time tracing on the menu, it introduced wrong dependencies with BLK_DEV_INITRD as below. WARNING: unmet direct dependencies detected for BOOT_CONFIG Depends on [n]: BLK_DEV_INITRD [=n] Selected by [y]: - BOOTTIME_TRACING [=y] && TRACING_SUPPORT [=y] && FTRACE [=y] && TRACING [=y] This makes the CONFIG_BOOT_CONFIG selects CONFIG_BLK_DEV_INITRD to fix this error and make CONFIG_BOOTTIME_TRACING=n by default, so that both boot-time tracing and boot configuration off but those appear on the menu list. Link: http://lkml.kernel.org/r/158264140162.23842.11237423518607465535.stgit@devnote2 Fixes: d8a953ddde5e ("bootconfig: Set CONFIG_BOOT_CONFIG=n by default") Reported-by: Randy Dunlap Compiled-tested-by: Randy Dunlap Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

bootconfig: Print array as multiple commands for legacy command line

2020-02-20T22:56:29Z

Print arraied values as multiple same options for legacy kernel command line. With this rule, if the "kernel.*" and "init.*" array entries in bootconfig are printed out as multiple same options, e.g. kernel { console = "ttyS0,115200" console += "tty0" } will be correctly converted to console="ttyS0,115200" console="tty0" in the kernel command line. Link: http://lkml.kernel.org/r/158220118213.26565.8163300497009463916.stgit@devnote2 Reported-by: Borislav Petkov Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

bootconfig: Add bootconfig magic word for indicating bootconfig explicitly

2020-02-20T22:52:34Z

Add bootconfig magic word to the end of bootconfig on initrd image for indicating explicitly the bootconfig is there. Also tools/bootconfig treats wrong size or wrong checksum or parse error as an error, because if there is a bootconfig magic word, there must be a bootconfig. The bootconfig magic word is "#BOOTCONFIG\n", 12 bytes word. Thus the block image of the initrd file with bootconfig is as follows. [Initrd][bootconfig][size][csum][#BOOTCONFIG\n] Link: http://lkml.kernel.org/r/158220112263.26565.3944814205960612841.stgit@devnote2 Suggested-by: Steven Rostedt Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

bootconfig: Set CONFIG_BOOT_CONFIG=n by default

2020-02-20T22:52:12Z

Set CONFIG_BOOT_CONFIG=n by default. This also warns user if CONFIG_BOOT_CONFIG=n but "bootconfig" is given in the kernel command line. Link: http://lkml.kernel.org/r/158220111291.26565.9036889083940367969.stgit@devnote2 Suggested-by: Steven Rostedt Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

bootconfig: Mark boot_config_checksum() static

2020-02-20T22:43:58Z

In fact, this function is only used in this file, so mark it with 'static'. Link: http://lkml.kernel.org/r/1581852511-14163-1-git-send-email-hqjagain@gmail.com Acked-by: Masami Hiramatsu Signed-off-by: Qiujun Huang Signed-off-by: Steven Rostedt (VMware)

Merge tag 'trace-v5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2020-02-12T00:39:18Z

Pull tracing fixes from Steven Rostedt: "Various fixes: - Fix an uninitialized variable - Fix compile bug to bootconfig userspace tool (in tools directory) - Suppress some error messages of bootconfig userspace tool - Remove unneded CONFIG_LIBXBC from bootconfig - Allocate bootconfig xbc_nodes dynamically. To ease complaints about taking up static memory at boot up - Use of parse_args() to parse bootconfig instead of strstr() usage Prevents issues of double quotes containing the interested string - Fix missing ring_buffer_nest_end() on synthetic event error path - Return zero not -EINVAL on soft disabled synthetic event (soft disabling must be the same as hard disabling, which returns zero) - Consolidate synthetic event code (remove duplicate code)" * tag 'trace-v5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Consolidate trace() functions tracing: Don't return -EINVAL when tracing soft disabled synth events tracing: Add missing nest end to synth_event_trace_start() error case tools/bootconfig: Suppress non-error messages bootconfig: Allocate xbc_nodes array dynamically bootconfig: Use parse_args() to find bootconfig and '--' tracing/kprobe: Fix uninitialized variable bug bootconfig: Remove unneeded CONFIG_LIBXBC tools/bootconfig: Fix wrong __VA_ARGS__ usage

bootconfig: Use parse_args() to find bootconfig and '--'

2020-02-10T17:07:42Z

The current implementation does a naive search of "bootconfig" on the kernel command line. But this could find "bootconfig" that is part of another option in quotes (although highly unlikely). But it also needs to find '--' on the kernel command line to know if it should append a '--' or not when a bootconfig in the initrd file has an "init" section. The check uses the naive strstr() to find to see if it exists. But this can return a false positive if it exists in an option and then the "init" section in the initrd will not be appended properly. Using parse_args() to find both of these will solve both of these problems. Link: https://lore.kernel.org/r/202002070954.C18E7F58B@keescook Fixes: 7495e0926fdf3 ("bootconfig: Only load bootconfig if "bootconfig" is on the kernel cmdline") Fixes: 1319916209ce8 ("bootconfig: init: Allow admin to use bootconfig for init command line") Reported-by: Kees Cook Reviewed-by: Kees Cook Acked-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)