Revision c0cf4512a31eb3cec70b066bc36ed55f7d05b8c0 authored by Bart Van Assche on 23 June 2016, 07:35:48 UTC, committed by Doug Ledford on 23 June 2016, 16:04:09 UTC
The memory needed for the send and receive queues associated with
a QP is proportional to the max_sge parameter. The current value
of that parameter is such that with an mlx4 HCA the QP buffer size
is 8 MB. Since DMA is used for communication between HCA and CPU
that buffer either has to be allocated coherently or map_single()
must succeed for that buffer. Since large contiguous allocations
are fragile and since the maximum segment size for e.g. swiotlb
is 256 KB, reduce the max_sge parameter. This patch avoids that
the following text appears on the console after SRP logout and
relogin on a system equipped with multiple IB HCAs:

mlx4_core 0000:05:00.0: swiotlb buffer is full (sz: 8388608 bytes)
swiotlb: coherent allocation failed for device 0000:05:00.0 size=8388608
CPU: 11 PID: 148 Comm: kworker/11:1 Not tainted 4.7.0-rc4-dbg+ #1
Call Trace:
 [<ffffffff812c6d35>] dump_stack+0x67/0x92
 [<ffffffff812efe71>] swiotlb_alloc_coherent+0x141/0x150
 [<ffffffff810458be>] x86_swiotlb_alloc_coherent+0x3e/0x50
 [<ffffffffa03861fa>] mlx4_buf_direct_alloc.isra.5+0x9a/0x120 [mlx4_core]
 [<ffffffffa0386545>] mlx4_buf_alloc+0x165/0x1a0 [mlx4_core]
 [<ffffffffa035053d>] create_qp_common.isra.29+0x57d/0xff0 [mlx4_ib]
 [<ffffffffa03510da>] mlx4_ib_create_qp+0x12a/0x3f0 [mlx4_ib]
 [<ffffffffa031154a>] ib_create_qp+0x3a/0x250 [ib_core]
 [<ffffffffa055dd4b>] srpt_cm_handler+0x4bb/0xcad [ib_srpt]
 [<ffffffffa02c1ab0>] cm_process_work+0x20/0xf0 [ib_cm]
 [<ffffffffa02c3640>] cm_work_handler+0x1ac0/0x2059 [ib_cm]
 [<ffffffff810737ed>] process_one_work+0x19d/0x490
 [<ffffffff81073b29>] worker_thread+0x49/0x490
 [<ffffffff8107a0ea>] kthread+0xea/0x100
 [<ffffffff815b25af>] ret_from_fork+0x1f/0x40

Fixes: b99f8e4d7bcd ("IB/srpt: convert to the generic RDMA READ/WRITE API")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Doug Ledford <dledford@redhat.com>
1 parent 37e07cd
Raw File
Kconfig
menu "Certificates for signature checking"

config MODULE_SIG_KEY
	string "File name or PKCS#11 URI of module signing key"
	default "certs/signing_key.pem"
	depends on MODULE_SIG
	help
         Provide the file name of a private key/certificate in PEM format,
         or a PKCS#11 URI according to RFC7512. The file should contain, or
         the URI should identify, both the certificate and its corresponding
         private key.

         If this option is unchanged from its default "certs/signing_key.pem",
         then the kernel will automatically generate the private key and
         certificate as described in Documentation/module-signing.txt

config SYSTEM_TRUSTED_KEYRING
	bool "Provide system-wide ring of trusted keys"
	depends on KEYS
	depends on ASYMMETRIC_KEY_TYPE
	help
	  Provide a system keyring to which trusted keys can be added.  Keys in
	  the keyring are considered to be trusted.  Keys may be added at will
	  by the kernel from compiled-in data and from hardware key stores, but
	  userspace may only add extra keys if those keys can be verified by
	  keys already in the keyring.

	  Keys in this keyring are used by module signature checking.

config SYSTEM_TRUSTED_KEYS
	string "Additional X.509 keys for default system keyring"
	depends on SYSTEM_TRUSTED_KEYRING
	help
	  If set, this option should be the filename of a PEM-formatted file
	  containing trusted X.509 certificates to be included in the default
	  system keyring. Any certificate used for module signing is implicitly
	  also trusted.

	  NOTE: If you previously provided keys for the system keyring in the
	  form of DER-encoded *.x509 files in the top-level build directory,
	  those are no longer used. You will need to set this option instead.

config SYSTEM_EXTRA_CERTIFICATE
	bool "Reserve area for inserting a certificate without recompiling"
	depends on SYSTEM_TRUSTED_KEYRING
	help
	  If set, space for an extra certificate will be reserved in the kernel
	  image. This allows introducing a trusted certificate to the default
	  system keyring without recompiling the kernel.

config SYSTEM_EXTRA_CERTIFICATE_SIZE
	int "Number of bytes to reserve for the extra certificate"
	depends on SYSTEM_EXTRA_CERTIFICATE
	default 4096
	help
	  This is the number of bytes reserved in the kernel image for a
	  certificate to be inserted.

config SECONDARY_TRUSTED_KEYRING
	bool "Provide a keyring to which extra trustable keys may be added"
	depends on SYSTEM_TRUSTED_KEYRING
	help
	  If set, provide a keyring to which extra keys may be added, provided
	  those keys are not blacklisted and are vouched for by a key built
	  into the kernel or already in the secondary trusted keyring.

endmenu
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