From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
To: Michael Ellerman <mpe@ellerman.id.au>, linuxppc-dev@lists.ozlabs.org
Cc: linuxram@us.ibm.com, bauerman@linux.ibm.com
Subject: Re: [PATCH v5 23/26] powerpc/book3s64/kuap: Move UAMOR setup to key init function
Date: Tue, 07 Jul 2020 16:55:15 +0530 [thread overview]
Message-ID: <87d057k1no.fsf@linux.ibm.com> (raw)
In-Reply-To: <87fta35084.fsf@mpe.ellerman.id.au>
Michael Ellerman <mpe@ellerman.id.au> writes:
> "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> writes:
>
.....
>> @@ -232,8 +246,9 @@ void __init setup_kuap(bool disabled)
>> cur_cpu_spec->mmu_features |= MMU_FTR_KUAP;
>> }
>>
>> - /* Make sure userspace can't change the AMR */
>> - mtspr(SPRN_UAMOR, 0);
>
> Why not just leave it there. It's extra insurance and it's good
> documentation.
We can't se the value to 0, because with hash kuap it is derived
from what other keys are used for. Are you suggesting to keep it as
if (radix_enabled())
mtspr(SPRN_UAMOR, 0);
That would confuse w.r.t what happens with hash.
I can add a comment there explaining details?
>
>> + /*
>> + * Set the default kernel AMR values on all cpus.
>> + */
>> mtspr(SPRN_AMR, AMR_KUAP_BLOCKED);
>> isync();
>> }
>> @@ -278,11 +293,6 @@ static inline u64 read_uamor(void)
>> return mfspr(SPRN_UAMOR);
>> }
>>
>> -static inline void write_uamor(u64 value)
>> -{
>> - mtspr(SPRN_UAMOR, value);
>> -}
>> -
>> static bool is_pkey_enabled(int pkey)
>> {
>> u64 uamor = read_uamor();
>> @@ -353,7 +363,6 @@ void thread_pkey_regs_save(struct thread_struct *thread)
>> */
>> thread->amr = read_amr();
>> thread->iamr = read_iamr();
>> - thread->uamor = read_uamor();
>> }
>>
>> void thread_pkey_regs_restore(struct thread_struct *new_thread,
>> @@ -366,8 +375,6 @@ void thread_pkey_regs_restore(struct thread_struct *new_thread,
>> write_amr(new_thread->amr);
>> if (old_thread->iamr != new_thread->iamr)
>> write_iamr(new_thread->iamr);
>> - if (old_thread->uamor != new_thread->uamor)
>> - write_uamor(new_thread->uamor);
>> }
>>
>> void thread_pkey_regs_init(struct thread_struct *thread)
>> @@ -377,11 +384,9 @@ void thread_pkey_regs_init(struct thread_struct *thread)
>>
>> thread->amr = default_amr;
>> thread->iamr = default_iamr;
>> - thread->uamor = default_uamor;
>>
>> write_amr(default_amr);
>> write_iamr(default_iamr);
>> - write_uamor(default_uamor);
>> }
>>
>> int execute_only_pkey(struct mm_struct *mm)
>
> cheers
-aneesh
next prev parent reply other threads:[~2020-07-07 11:29 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-19 13:58 [PATCH v5 00/26] powerpc/book3s/64/pkeys: Simplify the code Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 01/26] powerpc/book3s64/pkeys: Fixup bit numbering Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 02/26] powerpc/book3s64/pkeys: pkeys are supported only on hash on book3s Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 03/26] powerpc/book3s64/pkeys: Move pkey related bits in the linux page table Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 04/26] powerpc/book3s64/pkeys: Explain key 1 reservation details Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 05/26] powerpc/book3s64/pkeys: Simplify the key initialization Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 06/26] powerpc/book3s64/pkeys: Prevent key 1 modification from userspace Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 07/26] powerpc/book3s64/pkeys: kill cpu feature key CPU_FTR_PKEY Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 08/26] powerpc/book3s64/pkeys: Convert execute key support to static key Aneesh Kumar K.V
2020-07-06 7:19 ` Michael Ellerman
2020-07-06 8:47 ` Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 09/26] powerpc/book3s64/pkeys: Simplify pkey disable branch Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 10/26] powerpc/book3s64/pkeys: Convert pkey_total to max_pkey Aneesh Kumar K.V
2020-07-06 7:04 ` Michael Ellerman
2020-07-06 7:20 ` Aneesh Kumar K.V
2020-07-07 1:26 ` Michael Ellerman
2020-06-19 13:58 ` [PATCH v5 11/26] powerpc/book3s64/pkeys: Make initial_allocation_mask static Aneesh Kumar K.V
2020-07-06 7:04 ` Michael Ellerman
2020-07-06 8:48 ` Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 12/26] powerpc/book3s64/pkeys: Mark all the pkeys above max pkey as reserved Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 13/26] powerpc/book3s64/pkeys: Enable MMU_FTR_PKEY Aneesh Kumar K.V
2020-07-06 13:10 ` Michael Ellerman
2020-07-06 14:09 ` Aneesh Kumar K.V
2020-07-06 17:17 ` Aneesh Kumar K.V
2020-07-07 1:02 ` Michael Ellerman
2020-06-19 13:58 ` [PATCH v5 14/26] powerpc/book3s64/kuep: Add MMU_FTR_KUEP Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 15/26] powerpc/book3s64/pkeys: Use execute_pkey_disable static key Aneesh Kumar K.V
2020-07-06 7:20 ` Michael Ellerman
2020-07-06 8:49 ` Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 16/26] powerpc/book3s64/pkeys: Use MMU_FTR_PKEY instead of pkey_disabled " Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 17/26] powerpc/book3s64/keys: Print information during boot Aneesh Kumar K.V
2020-07-06 7:52 ` Michael Ellerman
2020-06-19 13:58 ` [PATCH v5 18/26] powerpc/book3s64/keys/kuap: Reset AMR/IAMR values on kexec Aneesh Kumar K.V
2020-07-06 12:29 ` Michael Ellerman
2020-07-06 14:39 ` Aneesh Kumar K.V
2020-07-07 1:07 ` Michael Ellerman
2020-06-19 13:58 ` [PATCH v5 19/26] powerpc/book3s64/kuap: Move KUAP related function outside radix Aneesh Kumar K.V
2020-07-06 12:41 ` Michael Ellerman
2020-07-06 14:41 ` Aneesh Kumar K.V
2020-07-07 1:22 ` Michael Ellerman
2020-06-19 13:58 ` [PATCH v5 20/26] powerpc/book3s64/kuep: Move KUEP " Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 21/26] powerpc/book3s64/kuap: Rename MMU_FTR_RADIX_KUAP to MMU_FTR_KUAP Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 22/26] powerpc/book3s64/kuap/kuep: Make KUAP and KUEP a subfeature of PPC_MEM_KEYS Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 23/26] powerpc/book3s64/kuap: Move UAMOR setup to key init function Aneesh Kumar K.V
2020-07-07 6:05 ` Michael Ellerman
2020-07-07 11:25 ` Aneesh Kumar K.V [this message]
2020-06-19 13:58 ` [PATCH v5 24/26] powerpc/selftest/ptrave-pkey: Rename variables to make it easier to follow code Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 25/26] powerpc/selftest/ptrace-pkey: Update the test to mark an invalid pkey correctly Aneesh Kumar K.V
2020-06-19 13:58 ` [PATCH v5 26/26] powerpc/selftest/ptrace-pkey: IAMR and uamor cannot be updated by ptrace Aneesh Kumar K.V
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