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  1. 22 1月, 2021 1 次提交
  3. 09 1月, 2021 1 次提交
    • D
      regulator: core: avoid regulator_resolve_supply() race condition · eaa7995c
      由 David Collins 提交于 
      The final step in regulator_register() is to call
regulator_resolve_supply() for each registered regulator
(including the one in the process of being registered).  The
regulator_resolve_supply() function first checks if rdev->supply
is NULL, then it performs various steps to try to find the supply.
If successful, rdev->supply is set inside of set_supply().

This procedure can encounter a race condition if two concurrent
tasks call regulator_register() near to each other on separate CPUs
and one of the regulators has rdev->supply_name specified.  There
is currently nothing guaranteeing atomicity between the rdev->supply
check and set steps.  Thus, both tasks can observe rdev->supply==NULL
in their regulator_resolve_supply() calls.  This then results in
both creating a struct regulator for the supply.  One ends up
actually stored in rdev->supply and the other is lost (though still
present in the supply's consumer_list).

Here is a kernel log snippet showing the issue:

[   12.421768] gpu_cc_gx_gdsc: supplied by pm8350_s5_level
[   12.425854] gpu_cc_gx_gdsc: supplied by pm8350_s5_level
[   12.429064] debugfs: Directory 'regulator.4-SUPPLY' with parent
               '17a00000.rsc:rpmh-regulator-gfxlvl-pm8350_s5_level'
               already present!

Avoid this race condition by holding the rdev->mutex lock inside
of regulator_resolve_supply() while checking and setting
rdev->supply.
Signed-off-by: NDavid Collins <collinsd@codeaurora.org>
Link: https://lore.kernel.org/r/1610068562-4410-1-git-send-email-collinsd@codeaurora.orgSigned-off-by: NMark Brown <broonie@kernel.org>
      eaa7995c
  5. 26 11月, 2020 1 次提交
  7. 14 11月, 2020 3 次提交
  9. 13 11月, 2020 3 次提交
  11. 11 11月, 2020 1 次提交
  13. 03 11月, 2020 1 次提交
  15. 29 10月, 2020 1 次提交
  17. 05 10月, 2020 1 次提交
  19. 02 10月, 2020 1 次提交
    • A
      regulator: core: Enlarge max OF property name length to 64 chars · e9bb4a06
      由 AngeloGioacchino Del Regno 提交于 
      Some regulator drivers may be defining very long names: this is the
case with the qcom_smd and qcom_spmi regulators, where we need to
parse the regulator parents from DT.

For clarity, this is an example:
{ "l13a", QCOM_SMD_RPM_LDOA, 13, &pm660_ht_lvpldo,
  "vdd_l8_l9_l10_l11_l12_l13_l14" },
pm660-regulators {
	...
	vdd_l8_l9_l10_l11_l12_l13_l14-supply = <&vreg_s4a_2p04>
	...
};
Now, with a 32 characters limit, the function is trying to parse,
exactly, "vdd_l8_l9_l10_l11_l12_l13_l14-s" (32 chars) instead of
the right one, which is 37 chars long in this specific case.

... And this is not only the case with PM660/PM660L, but also with
PMA8084, PM8916, PM8950 and others that are not implemented yet.

The length of 64 chars was chosen based on the longest parsed property
name that I could find, which is in PM8916, and would be 53 characters
long.
At that point, rounding that to 64 looked like being the best idea.
Signed-off-by: NAngeloGioacchino Del Regno <kholk11@gmail.com>
Link: https://lore.kernel.org/r/20200926125549.13191-2-kholk11@gmail.comSigned-off-by: NMark Brown <broonie@kernel.org>
      e9bb4a06
  21. 29 9月, 2020 3 次提交
  23. 22 9月, 2020 2 次提交
  25. 08 9月, 2020 1 次提交
  27. 01 9月, 2020 1 次提交
  29. 24 8月, 2020 1 次提交
  31. 19 8月, 2020 2 次提交
  33. 17 8月, 2020 7 次提交
  35. 24 7月, 2020 1 次提交
    • V
      regulator: fix memory leak on error path of regulator_register() · 9177514c
      由 Vladimir Zapolskiy 提交于 
      The change corrects registration and deregistration on error path
of a regulator, the problem was manifested by a reported memory
leak on deferred probe:

    as3722-regulator as3722-regulator: regulator 13 register failed -517

    # cat /sys/kernel/debug/kmemleak
    unreferenced object 0xecc43740 (size 64):
      comm "swapper/0", pid 1, jiffies 4294937640 (age 712.880s)
      hex dump (first 32 bytes):
        72 65 67 75 6c 61 74 6f 72 2e 32 34 00 5a 5a 5a  regulator.24.ZZZ
        5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a  ZZZZZZZZZZZZZZZZ
      backtrace:
        [<0c4c3d1c>] __kmalloc_track_caller+0x15c/0x2c0
        [<40c0ad48>] kvasprintf+0x64/0xd4
        [<109abd29>] kvasprintf_const+0x70/0x84
        [<c4215946>] kobject_set_name_vargs+0x34/0xa8
        [<62282ea2>] dev_set_name+0x40/0x64
        [<a39b6757>] regulator_register+0x3a4/0x1344
        [<16a9543f>] devm_regulator_register+0x4c/0x84
        [<51a4c6a1>] as3722_regulator_probe+0x294/0x754
        ...

The memory leak problem was introduced as a side ef another fix in
regulator_register() error path, I believe that the proper fix is
to decouple device_register() function into its two compounds and
initialize a struct device before assigning any values to its fields
and then using it before actual registration of a device happens.

This lets to call put_device() safely after initialization, and, since
now a release callback is called, kfree(rdev->constraints) shall be
removed to exclude a double free condition.

Fixes: a3cde953 ("regulator: core: fix regulator_register() error paths to properly release rdev")
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Cc: Wen Yang <wenyang@linux.alibaba.com>
Link: https://lore.kernel.org/r/20200724005013.23278-1-vz@mleia.comSigned-off-by: NMark Brown <broonie@kernel.org>
      9177514c
  37. 20 7月, 2020 1 次提交
  39. 15 7月, 2020 1 次提交
  41. 30 5月, 2020 1 次提交
  43. 29 5月, 2020 1 次提交
  45. 30 4月, 2020 1 次提交
  47. 14 4月, 2020 1 次提交
  49. 14 3月, 2020 1 次提交
  51. 05 3月, 2020 1 次提交
    • J
      regulator: Use driver_deferred_probe_timeout for regulator_init_complete_work · dca0b449
      由 John Stultz 提交于 
      The regulator_init_complete_work logic defers the cleanup for an
arbitrary 30 seconds of time to allow modules loaded by userland
to start.

This arbitrary timeout is similar to the
driver_deferred_probe_timeout value, and its been suggested we
align these so users have a method to extend the timeouts as
needed.

So this patch changes the logic to use the
driver_deferred_probe_timeout value for the delay value if it
is set (using a delay of 0 if it is not).

Cc: linux-pm@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Todd Kjos <tkjos@google.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Kevin Hilman <khilman@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Rob Herring <robh@kernel.org>
Acked-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
Link: https://lore.kernel.org/r/20200225050828.56458-7-john.stultz@linaro.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      dca0b449