[PATCH RFC rebase 7/9] powerpc/64: barrier_nospec: Add debugfs trigger
From: Michal Suchanek <hidden>
Date: 2018-03-15 19:15:56
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Copypasta from rfi implementation Signed-off-by: Michal Suchanek <redacted> --- arch/powerpc/kernel/setup_64.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+)
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index f60e0e3b5ad2..f6678a7b6114 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c@@ -963,6 +963,41 @@ static __init int rfi_flush_debugfs_init(void) return 0; } device_initcall(rfi_flush_debugfs_init); + +static int barrier_nospec_set(void *data, u64 val) +{ + switch (val) { + case 0: + case 1: + break; + default: + return -EINVAL; + } + + if (!!val == !!barrier_nospec_enabled) + return 0; + + barrier_nospec_enable(!!val); + + return 0; +} + +static int barrier_nospec_get(void *data, u64 *val) +{ + *val = barrier_nospec_enabled ? 1 : 0; + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(fops_barrier_nospec, + barrier_nospec_get, barrier_nospec_set, "%llu\n"); + +static __init int barrier_nospec_debugfs_init(void) +{ + debugfs_create_file("barrier_nospec", 0600, powerpc_debugfs_root, NULL, + &fops_barrier_nospec); + return 0; +} +device_initcall(barrier_nospec_debugfs_init); #endif ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
--
2.13.6