Adrian Huang d4c5da5049 dax: Fix stack overflow when mounting fsdax pmem device ... When mounting fsdax pmem device, commit 6180bb446a ("dax: fix detection of dax support for non-persistent memory block devices") introduces the stack overflow [1][2]. Here is the call path for mounting ext4 file system: ext4_fill_super bdev_dax_supported __bdev_dax_supported dax_supported generic_fsdax_supported __generic_fsdax_supported bdev_dax_supported The call path leads to the infinite calling loop, so we cannot call bdev_dax_supported() in __generic_fsdax_supported(). The sanity checking of the variable 'dax_dev' is moved prior to the two bdev_dax_pgoff() checks [3][4]. [1] https://lore.kernel.org/linux-nvdimm/1420999447.1004543.1600055488770.JavaMail.zimbra@redhat.com/ [2] https://lore.kernel.org/linux-nvdimm/alpine.LRH.2.02.2009141131220.30651@file01.intranet.prod.int.rdu2.redhat.com/ [3] https://lore.kernel.org/linux-nvdimm/CA+RJvhxBHriCuJhm-D8NvJRe3h2MLM+ZMFgjeJjrRPerMRLvdg@mail.gmail.com/ [4] https://lore.kernel.org/linux-nvdimm/20200903160608.GU878166@iweiny-DESK2.sc.intel.com/ Fixes: 6180bb446a ("dax: fix detection of dax support for non-persistent memory block devices") Reported-by: Yi Zhang <yi.zhang@redhat.com> Reported-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Adrian Huang <ahuang12@lenovo.com> Reviewed-by: Jan Kara <jack@suse.cz> Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> Cc: Coly Li <colyli@suse.de> Cc: Ira Weiny <ira.weiny@intel.com> Cc: John Pittman <jpittman@redhat.com> Link: https://lore.kernel.org/r/20200917111549.6367-1-adrianhuang0701@gmail.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>		2020-09-20 08:57:36 -07:00
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pmem	libnvdimm/namespace: Differentiate between probe mapping and runtime mapping	2019-11-14 19:08:47 -08:00
Kconfig	device-dax: Add a driver for "hmem" devices	2019-11-07 15:45:00 +01:00
Makefile	device-dax: Add a driver for "hmem" devices	2019-11-07 15:45:00 +01:00
bus.c	dax: Move mandatory ->zero_page_range() check in alloc_dax()	2020-04-02 19:15:03 -07:00
bus.h	dax: Fix alloc_dax_region() compile warning	2019-11-07 15:44:47 +01:00
dax-private.h	device-dax: add memory via add_memory_driver_managed()	2020-06-04 19:06:23 -07:00
device.c	memremap: rename MEMORY_DEVICE_DEVDAX to MEMORY_DEVICE_GENERIC	2020-09-04 09:59:59 +02:00
hmem.c	device-dax: Add a driver for "hmem" devices	2019-11-07 15:45:00 +01:00
kmem.c	device-dax: add memory via add_memory_driver_managed()	2020-06-04 19:06:23 -07:00
super.c	dax: Fix stack overflow when mounting fsdax pmem device	2020-09-20 08:57:36 -07:00