Commit Graph

8 Commits

Author SHA1 Message Date
Geert Uytterhoeven
6d4fabc6c7 PCI: Fix pci_register_io_range() memory leak
[ Upstream commit f6bda644fa3a7070621c3bf12cd657f69a42f170 ]

Kmemleak reports:

  unreferenced object 0xc328de40 (size 64):
    comm "kworker/1:1", pid 21, jiffies 4294938212 (age 1484.670s)
    hex dump (first 32 bytes):
      00 00 00 00 00 00 00 00 e0 d8 fc eb 00 00 00 00  ................
      00 00 10 fe 00 00 00 00 00 00 00 00 00 00 00 00  ................

  backtrace:
    [<ad758d10>] pci_register_io_range+0x3c/0x80
    [<2c7f139e>] of_pci_range_to_resource+0x48/0xc0
    [<f079ecc8>] devm_of_pci_get_host_bridge_resources.constprop.0+0x2ac/0x3ac
    [<e999753b>] devm_of_pci_bridge_init+0x60/0x1b8
    [<a895b229>] devm_pci_alloc_host_bridge+0x54/0x64
    [<e451ddb0>] rcar_pcie_probe+0x2c/0x644

In case a PCI host driver's probe is deferred, the same I/O range may be
allocated again, and be ignored, causing a memory leak.

Fix this by (a) letting logic_pio_register_range() return -EEXIST if the
passed range already exists, so pci_register_io_range() will free it, and
by (b) making pci_register_io_range() not consider -EEXIST an error
condition.

Link: https://lore.kernel.org/r/20210202100332.829047-1-geert+renesas@glider.be
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17 17:06:25 +01:00
John Garry
4acaa93ef6 logic_pio: Use _inX() and _outX()
Use _inX() and _outX(), which include memory barriers which may be
overridden per arch.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2020-05-07 14:54:26 +08:00
John Garry
26c4c6ce80 logic_pio: Improve macro argument name
Macro argument "bw" is used for building byte, word, and long-based
functions. Use "bwl" instead, to include long.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2020-05-07 14:54:23 +08:00
John Garry
0376fa72a4 lib: logic_pio: Enforce LOGIC_PIO_INDIRECT region ops are set at registration
Since the only LOGIC_PIO_INDIRECT host (hisi-lpc) now sets the ops prior
to registration, enforce this check for accessors ops at registration
instead of in the IO port accessors to simplify and marginally optimise
the code.

A slight misalignment is also tidied.

Also add myself as an author.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2019-11-05 08:45:25 +08:00
John Garry
b884e2de2a lib: logic_pio: Add logic_pio_unregister_range()
Add a function to unregister a logical PIO range.

Logical PIO space can still be leaked when unregistering certain
LOGIC_PIO_CPU_MMIO regions, but this acceptable for now since there are no
callers to unregister LOGIC_PIO_CPU_MMIO regions, and the logical PIO
region allocation scheme would need significant work to improve this.

Cc: stable@vger.kernel.org
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2019-08-13 14:54:24 +08:00
John Garry
0a27142bd1 lib: logic_pio: Avoid possible overlap for unregistering regions
The code was originally written to not support unregistering logical PIO
regions.

To accommodate supporting unregistering logical PIO regions, subtly modify
LOGIC_PIO_CPU_MMIO region registration code, such that the "end" of the
registered regions is the "end" of the last region, and not the sum of
the sizes of all the registered regions.

Cc: stable@vger.kernel.org
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2019-08-13 14:54:19 +08:00
John Garry
06709e81c6 lib: logic_pio: Fix RCU usage
The traversing of io_range_list with list_for_each_entry_rcu()
is not properly protected by rcu_read_lock() and rcu_read_unlock(),
so add them.

These functions mark the critical section scope where the list is
protected for the reader, it cannot be  "reclaimed". Any updater - in
this case, the logical PIO registration functions - cannot update the
list until the reader exits this critical section.

In addition, the list traversing used in logic_pio_register_range()
does not need to use the rcu variant.

This is because we are already using io_range_mutex to guarantee mutual
exclusion from mutating the list.

Cc: stable@vger.kernel.org
Fixes: 031e360186 ("lib: Add generic PIO mapping method")
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2019-08-13 14:48:54 +08:00
Zhichang Yuan
031e360186 lib: Add generic PIO mapping method
41f8bba7f5 ("of/pci: Add pci_register_io_range() and
pci_pio_to_address()") added support for PCI I/O space mapped into CPU
physical memory space.  With that support, the I/O ranges configured for
PCI/PCIe hosts on some architectures can be mapped to logical PIO and
converted easily between CPU address and the corresponding logical PIO.
Based on this, PCI I/O port space can be accessed via in/out accessors that
use memory read/write.

But on some platforms, there are bus hosts that access I/O port space with
host-local I/O port addresses rather than memory addresses.

Add a more generic I/O mapping method to support those devices.  With this
patch, both the CPU addresses and the host-local port can be mapped into
the logical PIO space with different logical/fake PIOs.  After this, all
the I/O accesses to either PCI MMIO devices or host-local I/O peripherals
can be unified into the existing I/O accessors defined in asm-generic/io.h
and be redirected to the right device-specific hooks based on the input
logical PIO.

Tested-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Zhichang Yuan <yuanzhichang@hisilicon.com>
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
[bhelgaas: remove -EFAULT return from logic_pio_register_range() per
https://lkml.kernel.org/r/20180403143909.GA21171@ulmo, fix NULL pointer
checking per https://lkml.kernel.org/r/20180403211505.GA29612@embeddedor.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2018-03-21 17:18:34 -05:00