From: Christophe Leroy <christophe.leroy@csgroup.eu>
To: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>,
Michael Ellerman <mpe@ellerman.id.au>,
Nicholas Piggin <npiggin@gmail.com>
Cc: "linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 29/37] powerpc/nohash: Replace pte_user() by pte_read()
Date: Mon, 6 Nov 2023 13:21:32 +0000 [thread overview]
Message-ID: <02c4b724-f503-31ea-eb77-4b3cd6776fd8@csgroup.eu> (raw)
In-Reply-To: <877cn39jyp.fsf@linux.ibm.com>
Le 31/10/2023 à 11:15, Aneesh Kumar K.V a écrit :
> Christophe Leroy <christophe.leroy@csgroup.eu> writes:
>
>> pte_user() is now only used in pte_access_permitted() to check
>> access on vmas. User flag is cleared to make a page unreadable.
>>
>> So rename it pte_read() and remove pte_user() which isn't used
>> anymore.
>>
>> For the time being it checks _PAGE_USER but in the near futur
>> all plateforms will be converted to _PAGE_READ so lets support
>> both for now.
>>
>> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>> ---
>> arch/powerpc/include/asm/nohash/32/pte-8xx.h | 7 -------
>> arch/powerpc/include/asm/nohash/pgtable.h | 13 +++++++------
>> arch/powerpc/mm/ioremap.c | 4 ----
>> 3 files changed, 7 insertions(+), 17 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/nohash/32/pte-8xx.h b/arch/powerpc/include/asm/nohash/32/pte-8xx.h
>> index 62c965a4511a..1ee38befd29a 100644
>> --- a/arch/powerpc/include/asm/nohash/32/pte-8xx.h
>> +++ b/arch/powerpc/include/asm/nohash/32/pte-8xx.h
>> @@ -112,13 +112,6 @@ static inline pte_t pte_mkwrite_novma(pte_t pte)
>>
>> #define pte_mkwrite_novma pte_mkwrite_novma
>>
>> -static inline bool pte_user(pte_t pte)
>> -{
>> - return !(pte_val(pte) & _PAGE_SH);
>> -}
>> -
>> -#define pte_user pte_user
>> -
>> static inline pte_t pte_mkhuge(pte_t pte)
>> {
>> return __pte(pte_val(pte) | _PAGE_SPS | _PAGE_HUGE);
>> diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h
>> index ee677162f9e6..aba56fe3b1c6 100644
>> --- a/arch/powerpc/include/asm/nohash/pgtable.h
>> +++ b/arch/powerpc/include/asm/nohash/pgtable.h
>> @@ -160,9 +160,6 @@ static inline int pte_write(pte_t pte)
>> return pte_val(pte) & _PAGE_WRITE;
>> }
>> #endif
>> -#ifndef pte_read
>> -static inline int pte_read(pte_t pte) { return 1; }
>> -#endif
>> static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; }
>> static inline int pte_special(pte_t pte) { return pte_val(pte) & _PAGE_SPECIAL; }
>> static inline int pte_none(pte_t pte) { return (pte_val(pte) & ~_PTE_NONE_MASK) == 0; }
>> @@ -190,10 +187,14 @@ static inline int pte_young(pte_t pte)
>> * and PTE_64BIT, PAGE_KERNEL_X contains _PAGE_BAP_SR which is also in
>> * _PAGE_USER. Need to explicitly match _PAGE_BAP_UR bit in that case too.
>> */
>> -#ifndef pte_user
>> -static inline bool pte_user(pte_t pte)
>> +#ifndef pte_read
>> +static inline bool pte_read(pte_t pte)
>> {
>> +#ifdef _PAGE_READ
>> + return (pte_val(pte) & _PAGE_READ) == _PAGE_READ;
>> +#else
>> return (pte_val(pte) & _PAGE_USER) == _PAGE_USER;
>> +#endif
>> }
>> #endif
>>
>> @@ -208,7 +209,7 @@ static inline bool pte_access_permitted(pte_t pte, bool write)
>> * A read-only access is controlled by _PAGE_USER bit.
>> * We have _PAGE_READ set for WRITE and EXECUTE
>> */
>> - if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte))
>> + if (!pte_present(pte) || !pte_read(pte))
>> return false;
>>
>> if (write && !pte_write(pte))
>> diff --git a/arch/powerpc/mm/ioremap.c b/arch/powerpc/mm/ioremap.c
>> index 7823c38f09de..7b0afcabd89f 100644
>> --- a/arch/powerpc/mm/ioremap.c
>> +++ b/arch/powerpc/mm/ioremap.c
>> @@ -50,10 +50,6 @@ void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long flags)
>> if (pte_write(pte))
>> pte = pte_mkdirty(pte);
>>
>> - /* we don't want to let _PAGE_USER leak out */
>> - if (WARN_ON(pte_user(pte)))
>> - return NULL;
>>
>
> This check is still valid right? I understand that we want to remove
> _PAGE_USER. But then loosing this check is ok?
Well, we may have to think about it for book3s/64. For all others
_PAGE_USER is gone and replaced by a check of addresses versus TASK_SIZE.
As ioremap() will map into vmalloc space that address is necesserally
correct.
>
>> -
>> if (iowa_is_active())
>> return iowa_ioremap(addr, size, pte_pgprot(pte), caller);
>> return __ioremap_caller(addr, size, pte_pgprot(pte), caller);
>> --
>> 2.41.0
next prev parent reply other threads:[~2023-11-06 13:22 UTC|newest]
Thread overview: 95+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-25 18:31 [PATCH v2 00/37] Implement execute-only protection on powerpc Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 01/37] powerpc/8xx: Fix pte_access_permitted() for PAGE_NONE Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 02/37] powerpc/64e: Fix wrong test in __ptep_test_and_clear_young() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 03/37] powerpc/40x: Remove stale PTE_ATOMIC_UPDATES macro Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 04/37] powerpc: Remove pte_ERROR() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 05/37] powerpc: Deduplicate prototypes of ptep_set_access_flags() and phys_mem_access_prot() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 06/37] powerpc: Refactor update_mmu_cache_range() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 07/37] powerpc: Untangle fixmap.h and pgtable.h and mmu.h Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 08/37] powerpc/nohash: Remove {pte/pmd}_protnone() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 09/37] powerpc/nohash: Refactor declaration of {map/unmap}_kernel_page() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 10/37] powerpc/nohash: Move 8xx version of pte_update() into pte-8xx.h Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 11/37] powerpc/nohash: Replace #ifdef CONFIG_44x by IS_ENABLED(CONFIG_44x) in pgtable.h Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 12/37] powerpc/nohash: Refactor pte_update() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 13/37] powerpc/nohash: Refactor checking of no-change in pte_update() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 14/37] powerpc/nohash: Deduplicate _PAGE_CHG_MASK Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 15/37] powerpc/nohash: Deduplicate pte helpers Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 16/37] powerpc/nohash: Refactor ptep_test_and_clear_young() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 17/37] powerpc/nohash: Deduplicate ptep_set_wrprotect() and ptep_get_and_clear() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 18/37] powerpc/nohash: Refactor pte_clear() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 19/37] powerpc/nohash: Refactor __ptep_set_access_flags() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 20/37] powerpc/e500: Simplify pte_mkexec() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 21/37] powerpc: Implement and use pgprot_nx() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 22/37] powerpc: Fail ioremap() instead of silently ignoring flags when PAGE_USER is set Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 23/37] powerpc: Remove pte_mkuser() and pte_mkpriviledged() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 24/37] powerpc: Rely on address instead of pte_user() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 25/37] powerpc: Refactor permission masks used for __P/__S table and kernel memory flags Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 26/37] powerpc/8xx: Use generic permission masks Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 27/37] powerpc/64s: " Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 28/37] powerpc/nohash: Add _PAGE_WRITE to supplement _PAGE_RW Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 29/37] powerpc/nohash: Replace pte_user() by pte_read() Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-10-31 10:15 ` Aneesh Kumar K.V
2023-10-31 10:15 ` Aneesh Kumar K.V
2023-11-06 13:21 ` Christophe Leroy [this message]
2023-11-07 13:34 ` Aneesh Kumar K.V
2023-11-09 18:20 ` Christophe Leroy
2023-11-13 10:23 ` Aneesh Kumar K.V
2023-11-23 15:55 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 30/37] powerpc/e500: Introduce _PAGE_READ and remove _PAGE_USER Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 31/37] powerpc/44x: " Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 32/37] powerpc/40x: " Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 33/37] powerpc/32s: Add _PAGE_WRITE to supplement _PAGE_RW Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 34/37] powerpc/32s: Introduce _PAGE_READ and remove _PAGE_USER Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 35/37] powerpc/ptdump: Display _PAGE_READ and _PAGE_WRITE Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 36/37] powerpc: Finally remove _PAGE_USER Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-09-25 18:31 ` [PATCH v2 37/37] powerpc: Support execute-only on all powerpc Christophe Leroy
2023-09-25 18:31 ` Christophe Leroy
2023-11-02 5:39 ` Aneesh Kumar K.V
2023-11-02 5:39 ` Aneesh Kumar K.V
2023-11-06 13:23 ` Christophe Leroy
2023-11-07 6:15 ` Aneesh Kumar K V
2023-11-07 6:15 ` Aneesh Kumar K V
2023-11-09 17:38 ` Christophe Leroy
2023-11-09 17:38 ` Christophe Leroy
2023-11-09 17:38 ` Christophe Leroy
2023-10-15 10:00 ` (subset) [PATCH v2 00/37] Implement execute-only protection on powerpc Michael Ellerman
2023-10-15 10:00 ` Michael Ellerman
2023-10-27 9:59 ` Michael Ellerman
2023-10-27 9:59 ` Michael Ellerman
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