c617e74f5b
[ Upstream commit 4253b0e0627ee3461e64c2495c616f1c8f6b127b ] The nospec-branch.c file is compiled without the gcc options to generate expoline thunks. The return branch of the sysfs show functions cpu_show_spectre_v1 and cpu_show_spectre_v2 is an indirect branch as well. These need to be compiled with expolines. Move the sysfs functions for spectre reporting to a separate file and loose an '.' for one of the messages. Cc: stable@vger.kernel.org # 4.16 Fixes: d424986f1d ("s390: add sysfs attributes for spectre") Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
21 lines
691 B
C
21 lines
691 B
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/device.h>
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#include <linux/cpu.h>
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#include <asm/facility.h>
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#include <asm/nospec-branch.h>
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ssize_t cpu_show_spectre_v1(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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return sprintf(buf, "Mitigation: __user pointer sanitization\n");
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}
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ssize_t cpu_show_spectre_v2(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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if (IS_ENABLED(CC_USING_EXPOLINE) && !nospec_disable)
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return sprintf(buf, "Mitigation: execute trampolines\n");
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if (__test_facility(82, S390_lowcore.alt_stfle_fac_list))
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return sprintf(buf, "Mitigation: limited branch prediction\n");
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return sprintf(buf, "Vulnerable\n");
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}
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