| Message ID | 343c844bbc5081d13ee4c9aa27ff3118f607e1cc.1539092112.git.christophe.leroy@c-s.fr (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ban the use of _PAGE_XXX flags outside platform specific code | expand |
Christophe Leroy <christophe.leroy@c-s.fr> writes: > Get rid of platform specific _PAGE_XXXX in powerpc common code and > use helpers instead. > > mm/dump_linuxpagetables.c will be handled separately > > Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> > Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> > --- > arch/powerpc/include/asm/book3s/32/pgtable.h | 9 +++------ > arch/powerpc/include/asm/nohash/32/pgtable.h | 12 ++++++++---- > arch/powerpc/include/asm/nohash/pgtable.h | 3 +-- > arch/powerpc/mm/pgtable.c | 21 +++++++-------------- > arch/powerpc/mm/pgtable_32.c | 15 ++++++++------- > arch/powerpc/mm/pgtable_64.c | 14 +++++++------- > arch/powerpc/xmon/xmon.c | 12 +++++++----- > 7 files changed, 41 insertions(+), 45 deletions(-) So turns out this patch *also* breaks my p5020ds :) Even with patch 4 merged, see next. It's the same crash: pcieport 2000:00:00.0: AER enabled with IRQ 480 Unable to handle kernel paging request for data at address 0x8000080080080000 Faulting instruction address: 0xc0000000000192cc Oops: Kernel access of bad area, sig: 11 [#1] BE SMP NR_CPUS=24 CoreNet Generic Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc3-gcc7x-g98c847323b3a #1 NIP: c0000000000192cc LR: c0000000005d0f9c CTR: 0000000000100000 REGS: c0000000f31bb400 TRAP: 0300 Not tainted (4.19.0-rc3-gcc7x-g98c847323b3a) MSR: 0000000080029000 <CE,EE,ME> CR: 24000224 XER: 00000000 DEAR: 8000080080080000 ESR: 0000000000800000 IRQMASK: 0 GPR00: c0000000005d0f84 c0000000f31bb688 c00000000117dc00 8000080080080000 GPR04: 0000000000000000 0000000000400000 00000ffbff241010 c0000000f31b8000 GPR08: 0000000000000000 0000000000100000 0000000000000000 c0000000012d4710 GPR12: 0000000084000422 c0000000012ff000 c000000000002774 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR24: 0000000000000000 0000000000000000 8000080080080000 c0000000ffff89a8 GPR28: c0000000f3576400 c0000000f3576410 0000000000400000 c0000000012ecc98 NIP [c0000000000192cc] ._memset_io+0x6c/0x9c LR [c0000000005d0f9c] .fsl_qman_probe+0x198/0x928 Call Trace: [c0000000f31bb688] [c0000000005d0f84] .fsl_qman_probe+0x180/0x928 (unreliable) [c0000000f31bb728] [c0000000006432ec] .platform_drv_probe+0x60/0xb4 [c0000000f31bb7a8] [c00000000064083c] .really_probe+0x294/0x35c [c0000000f31bb848] [c000000000640d2c] .__driver_attach+0x148/0x14c [c0000000f31bb8d8] [c00000000063d7dc] .bus_for_each_dev+0xb0/0x118 [c0000000f31bb988] [c00000000063ff28] .driver_attach+0x34/0x4c [c0000000f31bba08] [c00000000063f648] .bus_add_driver+0x174/0x2bc [c0000000f31bbaa8] [c0000000006418bc] .driver_register+0x90/0x180 [c0000000f31bbb28] [c000000000643270] .__platform_driver_register+0x60/0x7c [c0000000f31bbba8] [c000000000ee2a70] .fsl_qman_driver_init+0x24/0x38 [c0000000f31bbc18] [c0000000000023fc] .do_one_initcall+0x64/0x2b8 [c0000000f31bbcf8] [c000000000e9f480] .kernel_init_freeable+0x3a8/0x494 [c0000000f31bbda8] [c000000000002798] .kernel_init+0x24/0x148 [c0000000f31bbe28] [c0000000000009e8] .ret_from_kernel_thread+0x58/0x70 Instruction dump: 4e800020 2ba50003 40dd003c 3925fffc 5488402e 7929f082 7d082378 39290001 550a801e 7d2903a6 7d4a4378 794a0020 <91430000> 38630004 4200fff8 70a50003 Comparing a working vs broken kernel, it seems to boil down to the fact that we're filtering out more PTE bits now that we use pte_pgprot() in ioremap_prot(). With the old code we get: ioremap_prot: addr 0xff800000 flags 0x241215 ioremap_prot: addr 0xff800000 flags 0x241215 map_kernel_page: ea 0x8000080080080000 pa 0xff800000 pte 0xff800241215 And now we get: ioremap_prot: addr 0xff800000 flags 0x241215 pte 0x241215 ioremap_prot: addr 0xff800000 pte 0x241215 ioremap_prot: addr 0xff800000 prot 0x241014 map_kernel_page: ea 0x8000080080080000 pa 0xff800000 pte 0xff800241014 So we're losing 0x201, which for nohash book3e is: #define _PAGE_PRESENT 0x000001 /* software: pte contains a translation */ #define _PAGE_PSIZE_4K 0x000200 I haven't worked out if it's one or both of those that matter. The question is what's the right way to fix it? Should pte_pgprot() not be filtering those bits out on book3e? cheers
On 10/17/2018 12:59 AM, Michael Ellerman wrote: > Christophe Leroy <christophe.leroy@c-s.fr> writes: > >> Get rid of platform specific _PAGE_XXXX in powerpc common code and >> use helpers instead. >> >> mm/dump_linuxpagetables.c will be handled separately >> >> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> >> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> >> --- >> arch/powerpc/include/asm/book3s/32/pgtable.h | 9 +++------ >> arch/powerpc/include/asm/nohash/32/pgtable.h | 12 ++++++++---- >> arch/powerpc/include/asm/nohash/pgtable.h | 3 +-- >> arch/powerpc/mm/pgtable.c | 21 +++++++-------------- >> arch/powerpc/mm/pgtable_32.c | 15 ++++++++------- >> arch/powerpc/mm/pgtable_64.c | 14 +++++++------- >> arch/powerpc/xmon/xmon.c | 12 +++++++----- >> 7 files changed, 41 insertions(+), 45 deletions(-) > > So turns out this patch *also* breaks my p5020ds :) > > Even with patch 4 merged, see next. > > It's the same crash: > > pcieport 2000:00:00.0: AER enabled with IRQ 480 > Unable to handle kernel paging request for data at address 0x8000080080080000 > Faulting instruction address: 0xc0000000000192cc > Oops: Kernel access of bad area, sig: 11 [#1] > BE SMP NR_CPUS=24 CoreNet Generic > Modules linked in: > CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc3-gcc7x-g98c847323b3a #1 > NIP: c0000000000192cc LR: c0000000005d0f9c CTR: 0000000000100000 > REGS: c0000000f31bb400 TRAP: 0300 Not tainted (4.19.0-rc3-gcc7x-g98c847323b3a) > MSR: 0000000080029000 <CE,EE,ME> CR: 24000224 XER: 00000000 > DEAR: 8000080080080000 ESR: 0000000000800000 IRQMASK: 0 > GPR00: c0000000005d0f84 c0000000f31bb688 c00000000117dc00 8000080080080000 > GPR04: 0000000000000000 0000000000400000 00000ffbff241010 c0000000f31b8000 > GPR08: 0000000000000000 0000000000100000 0000000000000000 c0000000012d4710 > GPR12: 0000000084000422 c0000000012ff000 c000000000002774 0000000000000000 > GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > GPR24: 0000000000000000 0000000000000000 8000080080080000 c0000000ffff89a8 > GPR28: c0000000f3576400 c0000000f3576410 0000000000400000 c0000000012ecc98 > NIP [c0000000000192cc] ._memset_io+0x6c/0x9c > LR [c0000000005d0f9c] .fsl_qman_probe+0x198/0x928 > Call Trace: > [c0000000f31bb688] [c0000000005d0f84] .fsl_qman_probe+0x180/0x928 (unreliable) > [c0000000f31bb728] [c0000000006432ec] .platform_drv_probe+0x60/0xb4 > [c0000000f31bb7a8] [c00000000064083c] .really_probe+0x294/0x35c > [c0000000f31bb848] [c000000000640d2c] .__driver_attach+0x148/0x14c > [c0000000f31bb8d8] [c00000000063d7dc] .bus_for_each_dev+0xb0/0x118 > [c0000000f31bb988] [c00000000063ff28] .driver_attach+0x34/0x4c > [c0000000f31bba08] [c00000000063f648] .bus_add_driver+0x174/0x2bc > [c0000000f31bbaa8] [c0000000006418bc] .driver_register+0x90/0x180 > [c0000000f31bbb28] [c000000000643270] .__platform_driver_register+0x60/0x7c > [c0000000f31bbba8] [c000000000ee2a70] .fsl_qman_driver_init+0x24/0x38 > [c0000000f31bbc18] [c0000000000023fc] .do_one_initcall+0x64/0x2b8 > [c0000000f31bbcf8] [c000000000e9f480] .kernel_init_freeable+0x3a8/0x494 > [c0000000f31bbda8] [c000000000002798] .kernel_init+0x24/0x148 > [c0000000f31bbe28] [c0000000000009e8] .ret_from_kernel_thread+0x58/0x70 > Instruction dump: > 4e800020 2ba50003 40dd003c 3925fffc 5488402e 7929f082 7d082378 39290001 > 550a801e 7d2903a6 7d4a4378 794a0020 <91430000> 38630004 4200fff8 70a50003 > > > Comparing a working vs broken kernel, it seems to boil down to the fact > that we're filtering out more PTE bits now that we use pte_pgprot() in > ioremap_prot(). > > With the old code we get: > ioremap_prot: addr 0xff800000 flags 0x241215 > ioremap_prot: addr 0xff800000 flags 0x241215 > map_kernel_page: ea 0x8000080080080000 pa 0xff800000 pte 0xff800241215 > > > And now we get: > ioremap_prot: addr 0xff800000 flags 0x241215 pte 0x241215 > ioremap_prot: addr 0xff800000 pte 0x241215 > ioremap_prot: addr 0xff800000 prot 0x241014 > map_kernel_page: ea 0x8000080080080000 pa 0xff800000 pte 0xff800241014 > > So we're losing 0x201, which for nohash book3e is: > > #define _PAGE_PRESENT 0x000001 /* software: pte contains a translation */ > #define _PAGE_PSIZE_4K 0x000200 > > > I haven't worked out if it's one or both of those that matter. At least missing _PAGE_PRESENT is an issue I believe. > > The question is what's the right way to fix it? Should pte_pgprot() not > be filtering those bits out on book3e? I think we should not use pte_pggrot() for that then. What about the below fix ? Christophe From: Christophe Leroy <christophe.leroy@c-s.fr> Date: Wed, 17 Oct 2018 05:56:25 +0000 Subject: [PATCH] powerpc/mm: don't use pte_pgprot() in ioremap_prot() pte_pgprot() filters out some required flags like _PAGE_PRESENT. This patch replaces pte_pgprot() by __pgprot(pte_val()) in ioremap_prot() Fixes: 26973fa5ac0e ("powerpc/mm: use pte helpers in generic code") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> --- arch/powerpc/mm/pgtable_32.c | 3 ++- arch/powerpc/mm/pgtable_64.c | 4 ++-- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index 5877f5aa8f5d..a606e2f4937b 100644 --- a/arch/powerpc/mm/pgtable_32.c +++ b/arch/powerpc/mm/pgtable_32.c @@ -122,7 +122,8 @@ ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags) pte = pte_exprotect(pte); pte = pte_mkprivileged(pte); - return __ioremap_caller(addr, size, pte_pgprot(pte), __builtin_return_address(0)); + return __ioremap_caller(addr, size, __pgprot(pte_val(pte)), + __builtin_return_address(0)); } EXPORT_SYMBOL(ioremap_prot); diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c index fb1375c07e8c..836bf436cabb 100644 --- a/arch/powerpc/mm/pgtable_64.c +++ b/arch/powerpc/mm/pgtable_64.c @@ -245,8 +245,8 @@ void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, pte = pte_mkprivileged(pte); if (ppc_md.ioremap) - return ppc_md.ioremap(addr, size, pte_pgprot(pte), caller); - return __ioremap_caller(addr, size, pte_pgprot(pte), caller); + return ppc_md.ioremap(addr, size, __pgprot(pte_val(pte)), caller); + return __ioremap_caller(addr, size, __pgprot(pte_val(pte)), caller); }
diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h index a6ca799e0eb5..a0dc3a3eef33 100644 --- a/arch/powerpc/include/asm/book3s/32/pgtable.h +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h @@ -331,17 +331,14 @@ static inline bool pte_ci(pte_t pte) #define pte_access_permitted pte_access_permitted static inline bool pte_access_permitted(pte_t pte, bool write) { - unsigned long pteval = pte_val(pte); /* * A read-only access is controlled by _PAGE_USER bit. * We have _PAGE_READ set for WRITE and EXECUTE */ - unsigned long need_pte_bits = _PAGE_PRESENT | _PAGE_USER; - - if (write) - need_pte_bits |= _PAGE_WRITE; + if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte)) + return false; - if ((pteval & need_pte_bits) != need_pte_bits) + if (write && !pte_write(pte)) return false; return true; diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h index 6fecfd7854f5..a4156da4a7a4 100644 --- a/arch/powerpc/include/asm/nohash/32/pgtable.h +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h @@ -277,7 +277,10 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - pte_update(ptep, (_PAGE_RW | _PAGE_HWWRITE), _PAGE_RO); + unsigned long clr = ~pte_val(pte_wrprotect(__pte(~0))); + unsigned long set = pte_val(pte_wrprotect(__pte(0))); + + pte_update(ptep, clr, set); } static inline void huge_ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) @@ -291,9 +294,10 @@ static inline void __ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address, int psize) { - unsigned long set = pte_val(entry) & - (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC); - unsigned long clr = ~pte_val(entry) & (_PAGE_RO | _PAGE_NA); + pte_t pte_set = pte_mkyoung(pte_mkdirty(pte_mkwrite(pte_mkexec(__pte(0))))); + pte_t pte_clr = pte_mkyoung(pte_mkdirty(pte_mkwrite(pte_mkexec(__pte(~0))))); + unsigned long set = pte_val(entry) & pte_val(pte_set); + unsigned long clr = ~pte_val(entry) & ~pte_val(pte_clr); pte_update(ptep, clr, set); diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h index b256e38a047c..062d96233673 100644 --- a/arch/powerpc/include/asm/nohash/pgtable.h +++ b/arch/powerpc/include/asm/nohash/pgtable.h @@ -32,8 +32,7 @@ static inline pgprot_t pte_pgprot(pte_t pte) { return __pgprot(pte_val(pte) & PA */ static inline int pte_protnone(pte_t pte) { - return (pte_val(pte) & - (_PAGE_PRESENT | _PAGE_USER)) == _PAGE_PRESENT; + return pte_present(pte) && !pte_user(pte); } static inline int pmd_protnone(pmd_t pmd) diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c index f97d9c3760e3..ca4b1f7ac39d 100644 --- a/arch/powerpc/mm/pgtable.c +++ b/arch/powerpc/mm/pgtable.c @@ -44,20 +44,13 @@ static inline int is_exec_fault(void) static inline int pte_looks_normal(pte_t pte) { -#if defined(CONFIG_PPC_BOOK3S_64) - if ((pte_val(pte) & (_PAGE_PRESENT | _PAGE_SPECIAL)) == _PAGE_PRESENT) { + if (pte_present(pte) && !pte_special(pte)) { if (pte_ci(pte)) return 0; if (pte_user(pte)) return 1; } return 0; -#else - return (pte_val(pte) & - (_PAGE_PRESENT | _PAGE_SPECIAL | _PAGE_NO_CACHE | _PAGE_USER | - _PAGE_PRIVILEGED)) == - (_PAGE_PRESENT | _PAGE_USER); -#endif } static struct page *maybe_pte_to_page(pte_t pte) @@ -117,7 +110,7 @@ static pte_t set_pte_filter(pte_t pte) struct page *pg; /* No exec permission in the first place, move on */ - if (!(pte_val(pte) & _PAGE_EXEC) || !pte_looks_normal(pte)) + if (!pte_exec(pte) || !pte_looks_normal(pte)) return pte; /* If you set _PAGE_EXEC on weird pages you're on your own */ @@ -137,7 +130,7 @@ static pte_t set_pte_filter(pte_t pte) } /* Else, we filter out _PAGE_EXEC */ - return __pte(pte_val(pte) & ~_PAGE_EXEC); + return pte_exprotect(pte); } static pte_t set_access_flags_filter(pte_t pte, struct vm_area_struct *vma, @@ -150,7 +143,7 @@ static pte_t set_access_flags_filter(pte_t pte, struct vm_area_struct *vma, * if necessary. Also if _PAGE_EXEC is already set, same deal, * we just bail out */ - if (dirty || (pte_val(pte) & _PAGE_EXEC) || !is_exec_fault()) + if (dirty || pte_exec(pte) || !is_exec_fault()) return pte; #ifdef CONFIG_DEBUG_VM @@ -176,7 +169,7 @@ static pte_t set_access_flags_filter(pte_t pte, struct vm_area_struct *vma, set_bit(PG_arch_1, &pg->flags); bail: - return __pte(pte_val(pte) | _PAGE_EXEC); + return pte_mkexec(pte); } #endif /* CONFIG_PPC_BOOK3S */ @@ -191,10 +184,10 @@ void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, * Make sure hardware valid bit is not set. We don't do * tlb flush for this update. */ - VM_WARN_ON(pte_val(*ptep) & _PAGE_PRESENT); + VM_WARN_ON(pte_hw_valid(*ptep)); /* Add the pte bit when trying to set a pte */ - pte = __pte(pte_val(pte) | _PAGE_PTE); + pte = pte_mkpte(pte); /* Note: mm->context.id might not yet have been assigned as * this context might not have been activated yet when this diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index 01f348938328..5877f5aa8f5d 100644 --- a/arch/powerpc/mm/pgtable_32.c +++ b/arch/powerpc/mm/pgtable_32.c @@ -112,15 +112,17 @@ EXPORT_SYMBOL(ioremap_coherent); void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags) { + pte_t pte = __pte(flags); + /* writeable implies dirty for kernel addresses */ - if ((flags & (_PAGE_RW | _PAGE_RO)) != _PAGE_RO) - flags |= _PAGE_DIRTY | _PAGE_HWWRITE; + if (pte_write(pte)) + pte = pte_mkdirty(pte); /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */ - flags &= ~(_PAGE_USER | _PAGE_EXEC); - flags |= _PAGE_PRIVILEGED; + pte = pte_exprotect(pte); + pte = pte_mkprivileged(pte); - return __ioremap_caller(addr, size, __pgprot(flags), __builtin_return_address(0)); + return __ioremap_caller(addr, size, pte_pgprot(pte), __builtin_return_address(0)); } EXPORT_SYMBOL(ioremap_prot); @@ -235,8 +237,7 @@ int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot) /* The PTE should never be already set nor present in the * hash table */ - BUG_ON((pte_val(*pg) & (_PAGE_PRESENT | _PAGE_HASHPTE)) && - pgprot_val(prot)); + BUG_ON((pte_present(*pg) | pte_hashpte(*pg)) && pgprot_val(prot)); set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, prot)); } smp_wmb(); diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c index b0f4a4b4f62b..fb1375c07e8c 100644 --- a/arch/powerpc/mm/pgtable_64.c +++ b/arch/powerpc/mm/pgtable_64.c @@ -230,23 +230,23 @@ void __iomem *ioremap_coherent(phys_addr_t addr, unsigned long size) void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags) { + pte_t pte = __pte(flags); void *caller = __builtin_return_address(0); /* writeable implies dirty for kernel addresses */ - if (flags & _PAGE_WRITE) - flags |= _PAGE_DIRTY; + if (pte_write(pte)) + pte = pte_mkdirty(pte); /* we don't want to let _PAGE_EXEC leak out */ - flags &= ~_PAGE_EXEC; + pte = pte_exprotect(pte); /* * Force kernel mapping. */ - flags &= ~_PAGE_USER; - flags |= _PAGE_PRIVILEGED; + pte = pte_mkprivileged(pte); if (ppc_md.ioremap) - return ppc_md.ioremap(addr, size, __pgprot(flags), caller); - return __ioremap_caller(addr, size, __pgprot(flags), caller); + return ppc_md.ioremap(addr, size, pte_pgprot(pte), caller); + return __ioremap_caller(addr, size, pte_pgprot(pte), caller); } diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c index c70d17c9a6ba..167271c7a97c 100644 --- a/arch/powerpc/xmon/xmon.c +++ b/arch/powerpc/xmon/xmon.c @@ -2993,15 +2993,17 @@ static void show_task(struct task_struct *tsk) #ifdef CONFIG_PPC_BOOK3S_64 void format_pte(void *ptep, unsigned long pte) { + pte_t entry = __pte(pte); + printf("ptep @ 0x%016lx = 0x%016lx\n", (unsigned long)ptep, pte); printf("Maps physical address = 0x%016lx\n", pte & PTE_RPN_MASK); printf("Flags = %s%s%s%s%s\n", - (pte & _PAGE_ACCESSED) ? "Accessed " : "", - (pte & _PAGE_DIRTY) ? "Dirty " : "", - (pte & _PAGE_READ) ? "Read " : "", - (pte & _PAGE_WRITE) ? "Write " : "", - (pte & _PAGE_EXEC) ? "Exec " : ""); + pte_young(entry) ? "Accessed " : "", + pte_dirty(entry) ? "Dirty " : "", + pte_read(entry) ? "Read " : "", + pte_write(entry) ? "Write " : "", + pte_exec(entry) ? "Exec " : ""); } static void show_pte(unsigned long addr)