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x86/fpu: Fix early FPU command-line parsing
authoryu-cheng yu <yu-cheng.yu@intel.com>
Wed, 6 Jan 2016 22:24:51 +0000 (14:24 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 16 Jun 2018 07:54:24 +0000 (09:54 +0200)
commitd1e6f6d18c80627415b399572c93e5ac5429f254
treefd25c6c0c24ae5a09a80ff5658dcebac54d7c692
parented90fd0cfe4ee5faa42a39605f430f13f39556da
x86/fpu: Fix early FPU command-line parsing

commit 4f81cbafcce2c603db7865e9d0e461f7947d77d4 upstream.

The function fpu__init_system() is executed before
parse_early_param(). This causes wrong FPU configuration. This
patch fixes this issue by parsing boot_command_line in the
beginning of fpu__init_system().

With all four patches in this series, each parameter disables
features as the following:

eagerfpu=off: eagerfpu, avx, avx2, avx512, mpx
no387: fpu
nofxsr: fxsr, fxsropt, xmm
noxsave: xsave, xsaveopt, xsaves, xsavec, avx, avx2, avx512,
mpx, xgetbv1 noxsaveopt: xsaveopt
noxsaves: xsaves

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: yu-cheng yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/1452119094-7252-2-git-send-email-yu-cheng.yu@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kernel/fpu/init.c