The following commit has been merged into the x86/fpu branch of tip: Commit-ID: b3607269ff57fd3c9690cb25962c5e4b91a0fd3b Gitweb: https://git.kernel.org/tip/b3607269ff57fd3c9690cb25962c5e4b91a0fd3b Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx> AuthorDate: Wed, 23 Jun 2021 14:01:29 +02:00 Committer: Borislav Petkov <bp@xxxxxxx> CommitterDate: Wed, 23 Jun 2021 17:49:45 +02:00 x86/pkeys: Revert a5eff7259790 ("x86/pkeys: Add PKRU value to init_fpstate") This cannot work and it's unclear how that ever made a difference. init_fpstate.xsave.header.xfeatures is always 0 so get_xsave_addr() will always return a NULL pointer, which will prevent storing the default PKRU value in init_fpstate. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Reviewed-by: Borislav Petkov <bp@xxxxxxx> Link: https://lkml.kernel.org/r/20210623121451.451391598@xxxxxxxxxxxxx --- arch/x86/kernel/cpu/common.c | 5 ----- arch/x86/mm/pkeys.c | 6 ------ 2 files changed, 11 deletions(-) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 9173dd4..dcbb11f 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -466,8 +466,6 @@ static bool pku_disabled; static __always_inline void setup_pku(struct cpuinfo_x86 *c) { - struct pkru_state *pk; - /* check the boot processor, plus compile options for PKU: */ if (!cpu_feature_enabled(X86_FEATURE_PKU)) return; @@ -478,9 +476,6 @@ static __always_inline void setup_pku(struct cpuinfo_x86 *c) return; cr4_set_bits(X86_CR4_PKE); - pk = get_xsave_addr(&init_fpstate.xsave, XFEATURE_PKRU); - if (pk) - pk->pkru = init_pkru_value; /* * Setting X86_CR4_PKE will cause the X86_FEATURE_OSPKE * cpuid bit to be set. We need to ensure that we diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c index a2332ee..a840ac7 100644 --- a/arch/x86/mm/pkeys.c +++ b/arch/x86/mm/pkeys.c @@ -10,7 +10,6 @@ #include <asm/cpufeature.h> /* boot_cpu_has, ... */ #include <asm/mmu_context.h> /* vma_pkey() */ -#include <asm/fpu/internal.h> /* init_fpstate */ int __execute_only_pkey(struct mm_struct *mm) { @@ -154,7 +153,6 @@ static ssize_t init_pkru_read_file(struct file *file, char __user *user_buf, static ssize_t init_pkru_write_file(struct file *file, const char __user *user_buf, size_t count, loff_t *ppos) { - struct pkru_state *pk; char buf[32]; ssize_t len; u32 new_init_pkru; @@ -177,10 +175,6 @@ static ssize_t init_pkru_write_file(struct file *file, return -EINVAL; WRITE_ONCE(init_pkru_value, new_init_pkru); - pk = get_xsave_addr(&init_fpstate.xsave, XFEATURE_PKRU); - if (!pk) - return -EINVAL; - pk->pkru = new_init_pkru; return count; }
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