From: Geert Uytterhoeven geert+renesas@glider.be
stable inclusion from linux-4.19.181 commit 6a8b02ead7f7ed10af3dbe180c524e0b5ce16c6e
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[ 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 Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com --- drivers/pci/pci.c | 4 ++++ lib/logic_pio.c | 3 +++ 2 files changed, 7 insertions(+)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 140c6bd328f8..f6e3a813caf1 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3834,6 +3834,10 @@ int pci_register_io_range(struct fwnode_handle *fwnode, phys_addr_t addr, ret = logic_pio_register_range(range); if (ret) kfree(range); + + /* Ignore duplicates due to deferred probing */ + if (ret == -EEXIST) + ret = 0; #endif
return ret; diff --git a/lib/logic_pio.c b/lib/logic_pio.c index 905027574e5d..774bb02fff10 100644 --- a/lib/logic_pio.c +++ b/lib/logic_pio.c @@ -27,6 +27,8 @@ static DEFINE_MUTEX(io_range_mutex); * @new_range: pointer to the IO range to be registered. * * Returns 0 on success, the error code in case of failure. + * If the range already exists, -EEXIST will be returned, which should be + * considered a success. * * Register a new IO range node in the IO range list. */ @@ -49,6 +51,7 @@ int logic_pio_register_range(struct logic_pio_hwaddr *new_range) list_for_each_entry(range, &io_range_list, list) { if (range->fwnode == new_range->fwnode) { /* range already there */ + ret = -EEXIST; goto end_register; } if (range->flags == LOGIC_PIO_CPU_MMIO &&