From ce578f16348b003675c928a1992498b33b515f18 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 23 Jun 2021 14:01:30 +0200 Subject: [PATCH] x86/fpu: Mark various FPU state variables __ro_after_init Nothing modifies these after booting. Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Reviewed-by: Borislav Petkov Reviewed-by: Andy Lutomirski Link: https://lkml.kernel.org/r/20210623121451.611751529@linutronix.de --- arch/x86/kernel/fpu/init.c | 4 ++-- arch/x86/kernel/fpu/xstate.c | 14 +++++++++----- 2 files changed, 11 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c index 701f196..95aa109 100644 --- a/arch/x86/kernel/fpu/init.c +++ b/arch/x86/kernel/fpu/init.c @@ -89,7 +89,7 @@ static void fpu__init_system_early_generic(struct cpuinfo_x86 *c) /* * Boot time FPU feature detection code: */ -unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu; +unsigned int mxcsr_feature_mask __ro_after_init = 0xffffffffu; EXPORT_SYMBOL_GPL(mxcsr_feature_mask); static void __init fpu__init_system_mxcsr(void) @@ -135,7 +135,7 @@ static void __init fpu__init_system_generic(void) * This is inherent to the XSAVE architecture which puts all state * components into a single, continuous memory block: */ -unsigned int fpu_kernel_xstate_size; +unsigned int fpu_kernel_xstate_size __ro_after_init; EXPORT_SYMBOL_GPL(fpu_kernel_xstate_size); /* Get alignment of the TYPE. */ diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index d822ce7..bcb9f56 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -61,17 +61,21 @@ static short xsave_cpuid_features[] __initdata = { */ u64 xfeatures_mask_all __read_mostly; -static unsigned int xstate_offsets[XFEATURE_MAX] = { [ 0 ... XFEATURE_MAX - 1] = -1}; -static unsigned int xstate_sizes[XFEATURE_MAX] = { [ 0 ... XFEATURE_MAX - 1] = -1}; -static unsigned int xstate_comp_offsets[XFEATURE_MAX] = { [ 0 ... XFEATURE_MAX - 1] = -1}; -static unsigned int xstate_supervisor_only_offsets[XFEATURE_MAX] = { [ 0 ... XFEATURE_MAX - 1] = -1}; +static unsigned int xstate_offsets[XFEATURE_MAX] __ro_after_init = + { [ 0 ... XFEATURE_MAX - 1] = -1}; +static unsigned int xstate_sizes[XFEATURE_MAX] __ro_after_init = + { [ 0 ... XFEATURE_MAX - 1] = -1}; +static unsigned int xstate_comp_offsets[XFEATURE_MAX] __ro_after_init = + { [ 0 ... XFEATURE_MAX - 1] = -1}; +static unsigned int xstate_supervisor_only_offsets[XFEATURE_MAX] __ro_after_init = + { [ 0 ... XFEATURE_MAX - 1] = -1}; /* * The XSAVE area of kernel can be in standard or compacted format; * it is always in standard format for user mode. This is the user * mode standard format size used for signal and ptrace frames. */ -unsigned int fpu_user_xstate_size; +unsigned int fpu_user_xstate_size __ro_after_init; /* * Return whether the system supports a given xfeature. -- 2.7.4