From mboxrd@z Thu Jan  1 00:00:00 1970
From: Fabrizio Demaria <fabrizio.f.demaria@gmail.com>
Subject: "crypto_hash_setkey" call from atomic context
Date: Thu, 10 Dec 2015 16:59:31 +0100
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Cc: "Nordell, Joakim" <joakim.nordell@intel.com>,
	"Chen, Shujuan" <shujuan.chen@intel.com>, doru.gucea@intel.com
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Hello,

I am investigating the current usage of kernel crypto-libraries in the
SCTP code, considering to adopt the same crypto framework for the
MPTCP implementation.

In sm_make_chunk.c, the crypto function "crypto_hash_setkey" is called
in an atomic context, despite the fact that this function CAN invoke a
GFP_KERNEL (sleeping) memory allocation. Calling a sleeping function
from an atomic context can end up in deadlock.
Is there a way to make sure that =E2=80=9Ccrypto_hash_setkey=E2=80=9D c=
an be safely
called in an atomic context, considering all the possible code-paths
followed by the function?

Thanks,
=46abrizio