On Fri, Oct 09, 2020 at 12:42:51PM -0700, ira.weiny@intel.com wrote:
From: Fenghua Yu fenghua.yu@intel.com
Define a helper, update_pkey_val(), which will be used to support both Protection Key User (PKU) and the new Protection Key for Supervisor (PKS) in subsequent patches.
Co-developed-by: Ira Weiny ira.weiny@intel.com Signed-off-by: Ira Weiny ira.weiny@intel.com Signed-off-by: Fenghua Yu fenghua.yu@intel.com
arch/x86/include/asm/pkeys.h | 2 ++ arch/x86/kernel/fpu/xstate.c | 22 ++++------------------ arch/x86/mm/pkeys.c | 21 +++++++++++++++++++++ 3 files changed, 27 insertions(+), 18 deletions(-)
This is not from Fenghua.
https://lkml.kernel.org/r/20200717085442.GX10769@hirez.programming.kicks-ass...
This is your patch based on the code I wrote.
diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c index f5efb4007e74..3cf8f775f36d 100644 --- a/arch/x86/mm/pkeys.c +++ b/arch/x86/mm/pkeys.c @@ -208,3 +208,24 @@ static __init int setup_init_pkru(char *opt) return 1; } __setup("init_pkru=", setup_init_pkru);
+/*
- Update the pk_reg value and return it.
- Kernel users use the same flags as user space:
PKEY_DISABLE_ACCESS
PKEY_DISABLE_WRITE- */
+u32 update_pkey_val(u32 pk_reg, int pkey, unsigned int flags) +{
- int pkey_shift = pkey * PKR_BITS_PER_PKEY;
- pk_reg &= ~(((1 << PKR_BITS_PER_PKEY) - 1) << pkey_shift);
- if (flags & PKEY_DISABLE_ACCESS)
pk_reg |= PKR_AD_BIT << pkey_shift;- if (flags & PKEY_DISABLE_WRITE)
pk_reg |= PKR_WD_BIT << pkey_shift;- return pk_reg;
+}
2.28.0.rc0.12.gb6a658bd00c9