* [PATCH stable 4.9 0/2] zsmalloc MAX_POSSIBLE_PHYSMEM_BITS @ 2021-11-03 20:57 Florian Fainelli 2021-11-03 20:57 ` [PATCH stable 4.9 1/2] mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS Florian Fainelli 2021-11-03 20:57 ` [PATCH stable 4.9 2/2] arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed Florian Fainelli 0 siblings, 2 replies; 5+ messages in thread From: Florian Fainelli @ 2021-11-03 20:57 UTC (permalink / raw) To: linux-kernel Cc: open list:MIPS, Sergey Senozhatsky, Stefan Agner, open list:ZSMALLOC COMPRESSED SLAB MEMORY ALLOCATOR, Paul Mackerras, Ralf Baechle, H. Peter Anvin, Sasha Levin, Florian Fainelli, maintainer:X86 ARCHITECTURE 32-BIT AND 64-BIT, Russell King, Mike Rapoport, Ingo Molnar, open list:SYNOPSYS ARC ARCHITECTURE, Nitin Gupta, open list:GENERIC INCLUDE/ASM HEADER FILES, Arnd Bergmann, Thomas Gleixner, moderated list:ARM PORT, Thomas Bogendoerfer, Greg Kroah-Hartman, stable, Minchan Kim, Vineet Gupta, open list:LINUX FOR POWERPC 32-BIT AND 64-BIT, Kirill A. Shutemov This patch series is a back port necessary to address the problem reported by Stefan Agner: https://lore.kernel.org/linux-mm/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@agner.ch/ but which ended up being addressed by Arnd in a slightly different way from Stefan's submission. The first patch from Kirill is back ported in order to have MAX_POSSIBLE_PHYSMEM_BITS be acted on my the zsmalloc.c code. Arnd Bergmann (1): arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed Kirill A. Shutemov (1): mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS arch/arc/include/asm/pgtable.h | 2 ++ arch/arm/include/asm/pgtable-2level.h | 2 ++ arch/arm/include/asm/pgtable-3level.h | 2 ++ arch/mips/include/asm/pgtable-32.h | 3 +++ arch/powerpc/include/asm/pte-common.h | 2 ++ arch/x86/include/asm/pgtable-3level_types.h | 1 + include/asm-generic/pgtable.h | 13 +++++++++++++ mm/zsmalloc.c | 13 +++++++------ 8 files changed, 32 insertions(+), 6 deletions(-) -- 2.25.1 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH stable 4.9 1/2] mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS 2021-11-03 20:57 [PATCH stable 4.9 0/2] zsmalloc MAX_POSSIBLE_PHYSMEM_BITS Florian Fainelli @ 2021-11-03 20:57 ` Florian Fainelli 2021-11-04 8:34 ` Patch "mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS" has been added to the 4.9-stable tree gregkh 2021-11-03 20:57 ` [PATCH stable 4.9 2/2] arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed Florian Fainelli 1 sibling, 1 reply; 5+ messages in thread From: Florian Fainelli @ 2021-11-03 20:57 UTC (permalink / raw) To: linux-kernel Cc: open list:MIPS, Sergey Senozhatsky, Peter Zijlstra, Stefan Agner, linux-mm, Paul Mackerras, stable, H. Peter Anvin, Ingo Molnar, Sasha Levin, Florian Fainelli, open list:SYNOPSYS ARC ARCHITECTURE, maintainer:X86 ARCHITECTURE 32-BIT AND 64-BIT, Russell King, Mike Rapoport, Ingo Molnar, Borislav Petkov, Nitin Gupta, open list:GENERIC INCLUDE/ASM HEADER FILES, Arnd Bergmann, open list:LINUX FOR POWERPC 32-BIT AND 64-BIT, Thomas Gleixner, moderated list:ARM PORT, Thomas Bogendoerfer, Greg Kroah-Hartman, Ralf Baechle, Andy Lutomirski, Minchan Kim, Vineet Gupta, Linus Torvalds, Kirill A. Shutemov From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> commit 02390b87a9459937cdb299e6b34ff33992512ec7 upstream With boot-time switching between paging mode we will have variable MAX_PHYSMEM_BITS. Let's use the maximum variable possible for CONFIG_X86_5LEVEL=y configuration to define zsmalloc data structures. The patch introduces MAX_POSSIBLE_PHYSMEM_BITS to cover such case. It also suits well to handle PAE special case. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Nitin Gupta <ngupta@vflare.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20180214111656.88514-3-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> [florian: drop arch/x86/include/asm/pgtable_64_types.h changes since there is no CONFIG_X86_5LEVEL] Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> --- arch/x86/include/asm/pgtable-3level_types.h | 1 + mm/zsmalloc.c | 13 +++++++------ 2 files changed, 8 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/pgtable-3level_types.h b/arch/x86/include/asm/pgtable-3level_types.h index bcc89625ebe5..f3f719d59e61 100644 --- a/arch/x86/include/asm/pgtable-3level_types.h +++ b/arch/x86/include/asm/pgtable-3level_types.h @@ -42,5 +42,6 @@ typedef union { */ #define PTRS_PER_PTE 512 +#define MAX_POSSIBLE_PHYSMEM_BITS 36 #endif /* _ASM_X86_PGTABLE_3LEVEL_DEFS_H */ diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 8db3c2b27a17..2b7bfd97587a 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -83,18 +83,19 @@ * This is made more complicated by various memory models and PAE. */ -#ifndef MAX_PHYSMEM_BITS -#ifdef CONFIG_HIGHMEM64G -#define MAX_PHYSMEM_BITS 36 -#else /* !CONFIG_HIGHMEM64G */ +#ifndef MAX_POSSIBLE_PHYSMEM_BITS +#ifdef MAX_PHYSMEM_BITS +#define MAX_POSSIBLE_PHYSMEM_BITS MAX_PHYSMEM_BITS +#else /* * If this definition of MAX_PHYSMEM_BITS is used, OBJ_INDEX_BITS will just * be PAGE_SHIFT */ -#define MAX_PHYSMEM_BITS BITS_PER_LONG +#define MAX_POSSIBLE_PHYSMEM_BITS BITS_PER_LONG #endif #endif -#define _PFN_BITS (MAX_PHYSMEM_BITS - PAGE_SHIFT) + +#define _PFN_BITS (MAX_POSSIBLE_PHYSMEM_BITS - PAGE_SHIFT) /* * Memory for allocating for handle keeps object position by -- 2.25.1 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Patch "mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS" has been added to the 4.9-stable tree 2021-11-03 20:57 ` [PATCH stable 4.9 1/2] mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS Florian Fainelli @ 2021-11-04 8:34 ` gregkh 0 siblings, 0 replies; 5+ messages in thread From: gregkh @ 2021-11-04 8:34 UTC (permalink / raw) To: arnd, benh, bp, f.fainelli, gregkh, hpa, kirill.shutemov, linux-arm-kernel, linux-mips, linux-mm, linux-snps-arc, linux, linuxppc-dev, luto, minchan, mingo, mingo, mpe, ngupta, paulus, peterz, ralf, rppt, sashal, sergey.senozhatsky.work, stefan, tglx, torvalds, tsbogend, vgupta, x86 Cc: stable-commits This is a note to let you know that I've just added the patch titled mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mm-zsmalloc-prepare-to-variable-max_physmem_bits.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@vger.kernel.org> know about it. From foo@baz Thu Nov 4 09:33:49 AM CET 2021 From: Florian Fainelli <f.fainelli@gmail.com> Date: Wed, 3 Nov 2021 13:57:13 -0700 Subject: mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS To: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Sasha Levin <sashal@kernel.org>, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, Nitin Gupta <ngupta@vflare.org>, Minchan Kim <minchan@kernel.org>, Andy Lutomirski <luto@amacapital.net>, Borislav Petkov <bp@suse.de>, Linus Torvalds <torvalds@linux-foundation.org>, Peter Zijlstra <peterz@infradead.org>, Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>, Thomas Gleixner <tglx@linutronix.de>, linux-mm@kvack.org, Ingo Molnar <mingo@kernel.org>, Florian Fainelli <f.fainelli@gmail.com>, Vineet Gupta <vgupta@synopsys.com>, Russell King <linux@armlinux.org.uk>, Ralf Baechle <ralf@linux-mips.org>, Benjamin Herrenschmidt <benh@kernel.crashing.org>, Paul Mackerras <paulus@samba.org>, Michael Ellerman <mpe@ellerman.id.au>, Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)), Arnd Bergmann <arnd@arndb.de>, Thomas Bogendoerfer <tsb ogend@alpha.franken.de>, Mike Rapoport <rppt@linux.ibm.com>, Stefan Agner <stefan@agner.ch>, linux-snps-arc@lists.infradead.org (open list:SYNOPSYS ARC ARCHITECTURE), linux-arm-kernel@lists.infradead.org (moderated list:ARM PORT), linux-mips@linux-mips.org (open list:MIPS), linuxppc-dev@lists.ozlabs.org (open list:LINUX FOR POWERPC (32-BIT AND 64-BIT)), linux-arch@vger.kernel.org (open list:GENERIC INCLUDE/ASM HEADER FILES) Message-ID: <20211103205714.374801-2-f.fainelli@gmail.com> From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> commit 02390b87a9459937cdb299e6b34ff33992512ec7 upstream With boot-time switching between paging mode we will have variable MAX_PHYSMEM_BITS. Let's use the maximum variable possible for CONFIG_X86_5LEVEL=y configuration to define zsmalloc data structures. The patch introduces MAX_POSSIBLE_PHYSMEM_BITS to cover such case. It also suits well to handle PAE special case. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Nitin Gupta <ngupta@vflare.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20180214111656.88514-3-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> [florian: drop arch/x86/include/asm/pgtable_64_types.h changes since there is no CONFIG_X86_5LEVEL] Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- arch/x86/include/asm/pgtable-3level_types.h | 1 + mm/zsmalloc.c | 13 +++++++------ 2 files changed, 8 insertions(+), 6 deletions(-) --- a/arch/x86/include/asm/pgtable-3level_types.h +++ b/arch/x86/include/asm/pgtable-3level_types.h @@ -42,5 +42,6 @@ typedef union { */ #define PTRS_PER_PTE 512 +#define MAX_POSSIBLE_PHYSMEM_BITS 36 #endif /* _ASM_X86_PGTABLE_3LEVEL_DEFS_H */ --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -83,18 +83,19 @@ * This is made more complicated by various memory models and PAE. */ -#ifndef MAX_PHYSMEM_BITS -#ifdef CONFIG_HIGHMEM64G -#define MAX_PHYSMEM_BITS 36 -#else /* !CONFIG_HIGHMEM64G */ +#ifndef MAX_POSSIBLE_PHYSMEM_BITS +#ifdef MAX_PHYSMEM_BITS +#define MAX_POSSIBLE_PHYSMEM_BITS MAX_PHYSMEM_BITS +#else /* * If this definition of MAX_PHYSMEM_BITS is used, OBJ_INDEX_BITS will just * be PAGE_SHIFT */ -#define MAX_PHYSMEM_BITS BITS_PER_LONG +#define MAX_POSSIBLE_PHYSMEM_BITS BITS_PER_LONG #endif #endif -#define _PFN_BITS (MAX_PHYSMEM_BITS - PAGE_SHIFT) + +#define _PFN_BITS (MAX_POSSIBLE_PHYSMEM_BITS - PAGE_SHIFT) /* * Memory for allocating for handle keeps object position by Patches currently in stable-queue which might be from f.fainelli@gmail.com are queue-4.9/mm-zsmalloc-prepare-to-variable-max_physmem_bits.patch queue-4.9/arch-pgtable-define-max_possible_physmem_bits-where-needed.patch ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH stable 4.9 2/2] arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed 2021-11-03 20:57 [PATCH stable 4.9 0/2] zsmalloc MAX_POSSIBLE_PHYSMEM_BITS Florian Fainelli 2021-11-03 20:57 ` [PATCH stable 4.9 1/2] mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS Florian Fainelli @ 2021-11-03 20:57 ` Florian Fainelli 2021-11-04 8:34 ` Patch "arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed" has been added to the 4.9-stable tree gregkh 1 sibling, 1 reply; 5+ messages in thread From: Florian Fainelli @ 2021-11-03 20:57 UTC (permalink / raw) To: linux-kernel Cc: open list:MIPS, Sergey Senozhatsky, Stefan Agner, open list:ZSMALLOC COMPRESSED SLAB MEMORY ALLOCATOR, Paul Mackerras, stable, H. Peter Anvin, Sasha Levin, Florian Fainelli, maintainer:X86 ARCHITECTURE 32-BIT AND 64-BIT, Russell King, Mike Rapoport, Ingo Molnar, open list:SYNOPSYS ARC ARCHITECTURE, Nitin Gupta, open list:GENERIC INCLUDE/ASM HEADER FILES, Arnd Bergmann, Thomas Gleixner, moderated list:ARM PORT, Thomas Bogendoerfer, Greg Kroah-Hartman, Ralf Baechle, Minchan Kim, Vineet Gupta, open list:LINUX FOR POWERPC 32-BIT AND 64-BIT, Kirill A. Shutemov From: Arnd Bergmann <arnd@arndb.de> [ Upstream commit cef397038167ac15d085914493d6c86385773709 ] Stefan Agner reported a bug when using zsram on 32-bit Arm machines with RAM above the 4GB address boundary: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = a27bd01c [00000000] *pgd=236a0003, *pmd=1ffa64003 Internal error: Oops: 207 [#1] SMP ARM Modules linked in: mdio_bcm_unimac(+) brcmfmac cfg80211 brcmutil raspberrypi_hwmon hci_uart crc32_arm_ce bcm2711_thermal phy_generic genet CPU: 0 PID: 123 Comm: mkfs.ext4 Not tainted 5.9.6 #1 Hardware name: BCM2711 PC is at zs_map_object+0x94/0x338 LR is at zram_bvec_rw.constprop.0+0x330/0xa64 pc : [<c0602b38>] lr : [<c0bda6a0>] psr: 60000013 sp : e376bbe0 ip : 00000000 fp : c1e2921c r10: 00000002 r9 : c1dda730 r8 : 00000000 r7 : e8ff7a00 r6 : 00000000 r5 : 02f9ffa0 r4 : e3710000 r3 : 000fdffe r2 : c1e0ce80 r1 : ebf979a0 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5383d Table: 235c2a80 DAC: fffffffd Process mkfs.ext4 (pid: 123, stack limit = 0x495a22e6) Stack: (0xe376bbe0 to 0xe376c000) As it turns out, zsram needs to know the maximum memory size, which is defined in MAX_PHYSMEM_BITS when CONFIG_SPARSEMEM is set, or in MAX_POSSIBLE_PHYSMEM_BITS on the x86 architecture. The same problem will be hit on all 32-bit architectures that have a physical address space larger than 4GB and happen to not enable sparsemem and include asm/sparsemem.h from asm/pgtable.h. After the initial discussion, I suggested just always defining MAX_POSSIBLE_PHYSMEM_BITS whenever CONFIG_PHYS_ADDR_T_64BIT is set, or provoking a build error otherwise. This addresses all configurations that can currently have this runtime bug, but leaves all other configurations unchanged. I looked up the possible number of bits in source code and datasheets, here is what I found: - on ARC, CONFIG_ARC_HAS_PAE40 controls whether 32 or 40 bits are used - on ARM, CONFIG_LPAE enables 40 bit addressing, without it we never support more than 32 bits, even though supersections in theory allow up to 40 bits as well. - on MIPS, some MIPS32r1 or later chips support 36 bits, and MIPS32r5 XPA supports up to 60 bits in theory, but 40 bits are more than anyone will ever ship - On PowerPC, there are three different implementations of 36 bit addressing, but 32-bit is used without CONFIG_PTE_64BIT - On RISC-V, the normal page table format can support 34 bit addressing. There is no highmem support on RISC-V, so anything above 2GB is unused, but it might be useful to eventually support CONFIG_ZRAM for high pages. Fixes: 61989a80fb3a ("staging: zsmalloc: zsmalloc memory allocation library") Fixes: 02390b87a945 ("mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS") Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Reviewed-by: Stefan Agner <stefan@agner.ch> Tested-by: Stefan Agner <stefan@agner.ch> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Link: https://lore.kernel.org/linux-mm/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@agner.ch/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Sasha Levin <sashal@kernel.org> [florian: patch arch/powerpc/include/asm/pte-common.h for 4.9.y removed arch/riscv/include/asm/pgtable.h which does not exist] Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> --- arch/arc/include/asm/pgtable.h | 2 ++ arch/arm/include/asm/pgtable-2level.h | 2 ++ arch/arm/include/asm/pgtable-3level.h | 2 ++ arch/mips/include/asm/pgtable-32.h | 3 +++ arch/powerpc/include/asm/pte-common.h | 2 ++ include/asm-generic/pgtable.h | 13 +++++++++++++ 6 files changed, 24 insertions(+) diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h index c10f5cb203e6..81198a6773c6 100644 --- a/arch/arc/include/asm/pgtable.h +++ b/arch/arc/include/asm/pgtable.h @@ -137,8 +137,10 @@ #ifdef CONFIG_ARC_HAS_PAE40 #define PTE_BITS_NON_RWX_IN_PD1 (0xff00000000 | PAGE_MASK | _PAGE_CACHEABLE) +#define MAX_POSSIBLE_PHYSMEM_BITS 40 #else #define PTE_BITS_NON_RWX_IN_PD1 (PAGE_MASK | _PAGE_CACHEABLE) +#define MAX_POSSIBLE_PHYSMEM_BITS 32 #endif /************************************************************************** diff --git a/arch/arm/include/asm/pgtable-2level.h b/arch/arm/include/asm/pgtable-2level.h index 92fd2c8a9af0..6154902bed83 100644 --- a/arch/arm/include/asm/pgtable-2level.h +++ b/arch/arm/include/asm/pgtable-2level.h @@ -78,6 +78,8 @@ #define PTE_HWTABLE_OFF (PTE_HWTABLE_PTRS * sizeof(pte_t)) #define PTE_HWTABLE_SIZE (PTRS_PER_PTE * sizeof(u32)) +#define MAX_POSSIBLE_PHYSMEM_BITS 32 + /* * PMD_SHIFT determines the size of the area a second-level page table can map * PGDIR_SHIFT determines what a third-level page table entry can map diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h index 2a029bceaf2f..35807e611b6e 100644 --- a/arch/arm/include/asm/pgtable-3level.h +++ b/arch/arm/include/asm/pgtable-3level.h @@ -37,6 +37,8 @@ #define PTE_HWTABLE_OFF (0) #define PTE_HWTABLE_SIZE (PTRS_PER_PTE * sizeof(u64)) +#define MAX_POSSIBLE_PHYSMEM_BITS 40 + /* * PGDIR_SHIFT determines the size a top-level page table entry can map. */ diff --git a/arch/mips/include/asm/pgtable-32.h b/arch/mips/include/asm/pgtable-32.h index c0be540e83cb..2c6df5a92e1e 100644 --- a/arch/mips/include/asm/pgtable-32.h +++ b/arch/mips/include/asm/pgtable-32.h @@ -110,6 +110,7 @@ static inline void pmd_clear(pmd_t *pmdp) #if defined(CONFIG_XPA) +#define MAX_POSSIBLE_PHYSMEM_BITS 40 #define pte_pfn(x) (((unsigned long)((x).pte_high >> _PFN_SHIFT)) | (unsigned long)((x).pte_low << _PAGE_PRESENT_SHIFT)) static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) @@ -125,6 +126,7 @@ pfn_pte(unsigned long pfn, pgprot_t prot) #elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) +#define MAX_POSSIBLE_PHYSMEM_BITS 36 #define pte_pfn(x) ((unsigned long)((x).pte_high >> 6)) static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) @@ -139,6 +141,7 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) #else +#define MAX_POSSIBLE_PHYSMEM_BITS 32 #ifdef CONFIG_CPU_VR41XX #define pte_pfn(x) ((unsigned long)((x).pte >> (PAGE_SHIFT + 2))) #define pfn_pte(pfn, prot) __pte(((pfn) << (PAGE_SHIFT + 2)) | pgprot_val(prot)) diff --git a/arch/powerpc/include/asm/pte-common.h b/arch/powerpc/include/asm/pte-common.h index 4ba26dd259fd..0d81cd9dd60e 100644 --- a/arch/powerpc/include/asm/pte-common.h +++ b/arch/powerpc/include/asm/pte-common.h @@ -101,8 +101,10 @@ static inline bool pte_user(pte_t pte) */ #if defined(CONFIG_PPC32) && defined(CONFIG_PTE_64BIT) #define PTE_RPN_MASK (~((1ULL<<PTE_RPN_SHIFT)-1)) +#define MAX_POSSIBLE_PHYSMEM_BITS 36 #else #define PTE_RPN_MASK (~((1UL<<PTE_RPN_SHIFT)-1)) +#define MAX_POSSIBLE_PHYSMEM_BITS 32 #endif /* _PAGE_CHG_MASK masks of bits that are to be preserved across diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 0a4c2d4d9f8d..b43fa9d95a7a 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -847,6 +847,19 @@ static inline bool arch_has_pfn_modify_check(void) #define io_remap_pfn_range remap_pfn_range #endif +#if !defined(MAX_POSSIBLE_PHYSMEM_BITS) && !defined(CONFIG_64BIT) +#ifdef CONFIG_PHYS_ADDR_T_64BIT +/* + * ZSMALLOC needs to know the highest PFN on 32-bit architectures + * with physical address space extension, but falls back to + * BITS_PER_LONG otherwise. + */ +#error Missing MAX_POSSIBLE_PHYSMEM_BITS definition +#else +#define MAX_POSSIBLE_PHYSMEM_BITS 32 +#endif +#endif + #ifndef has_transparent_hugepage #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define has_transparent_hugepage() 1 -- 2.25.1 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Patch "arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed" has been added to the 4.9-stable tree 2021-11-03 20:57 ` [PATCH stable 4.9 2/2] arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed Florian Fainelli @ 2021-11-04 8:34 ` gregkh 0 siblings, 0 replies; 5+ messages in thread From: gregkh @ 2021-11-04 8:34 UTC (permalink / raw) To: arnd, benh, f.fainelli, gregkh, hpa, kirill.shutemov, linux-arm-kernel, linux-mips, linux-mm, linux-snps-arc, linux, linuxppc-dev, minchan, mingo, mpe, ngupta, paulus, ralf, rppt, sashal, sergey.senozhatsky.work, stefan, tglx, tsbogend, vgupta, x86 Cc: stable-commits This is a note to let you know that I've just added the patch titled arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arch-pgtable-define-max_possible_physmem_bits-where-needed.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@vger.kernel.org> know about it. From foo@baz Thu Nov 4 09:33:49 AM CET 2021 From: Florian Fainelli <f.fainelli@gmail.com> Date: Wed, 3 Nov 2021 13:57:14 -0700 Subject: arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed To: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Sasha Levin <sashal@kernel.org>, Arnd Bergmann <arnd@arndb.de>, Thomas Bogendoerfer <tsbogend@alpha.franken.de>, Stefan Agner <stefan@agner.ch>, Mike Rapoport <rppt@linux.ibm.com>, Florian Fainelli <f.fainelli@gmail.com>, Vineet Gupta <vgupta@synopsys.com>, Russell King <linux@armlinux.org.uk>, Ralf Baechle <ralf@linux-mips.org>, Benjamin Herrenschmidt <benh@kernel.crashing.org>, Paul Mackerras <paulus@samba.org>, Michael Ellerman <mpe@ellerman.id.au>, Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)), Minchan Kim <minchan@kernel.org>, Nitin Gupta <ngupta@vflare.org>, Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, linux-snps-arc@lists.infradead.org (open list:SYNOPSYS ARC ARCHITECTURE), linux-arm-kernel@lists.infradead.org (mod erated list:ARM PORT), linux-mips@linux-mips.org (open list:MIPS), linuxppc-dev@lists.ozlabs.org (open list:LINUX FOR POWERPC (32-BIT AND 64-BIT)), linux-arch@vger.kernel.org (open list:GENERIC INCLUDE/ASM HEADER FILES), linux-mm@kvack.org (open list:ZSMALLOC COMPRESSED SLAB MEMORY ALLOCATOR) Message-ID: <20211103205714.374801-3-f.fainelli@gmail.com> From: Arnd Bergmann <arnd@arndb.de> [ Upstream commit cef397038167ac15d085914493d6c86385773709 ] Stefan Agner reported a bug when using zsram on 32-bit Arm machines with RAM above the 4GB address boundary: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = a27bd01c [00000000] *pgd=236a0003, *pmd=1ffa64003 Internal error: Oops: 207 [#1] SMP ARM Modules linked in: mdio_bcm_unimac(+) brcmfmac cfg80211 brcmutil raspberrypi_hwmon hci_uart crc32_arm_ce bcm2711_thermal phy_generic genet CPU: 0 PID: 123 Comm: mkfs.ext4 Not tainted 5.9.6 #1 Hardware name: BCM2711 PC is at zs_map_object+0x94/0x338 LR is at zram_bvec_rw.constprop.0+0x330/0xa64 pc : [<c0602b38>] lr : [<c0bda6a0>] psr: 60000013 sp : e376bbe0 ip : 00000000 fp : c1e2921c r10: 00000002 r9 : c1dda730 r8 : 00000000 r7 : e8ff7a00 r6 : 00000000 r5 : 02f9ffa0 r4 : e3710000 r3 : 000fdffe r2 : c1e0ce80 r1 : ebf979a0 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5383d Table: 235c2a80 DAC: fffffffd Process mkfs.ext4 (pid: 123, stack limit = 0x495a22e6) Stack: (0xe376bbe0 to 0xe376c000) As it turns out, zsram needs to know the maximum memory size, which is defined in MAX_PHYSMEM_BITS when CONFIG_SPARSEMEM is set, or in MAX_POSSIBLE_PHYSMEM_BITS on the x86 architecture. The same problem will be hit on all 32-bit architectures that have a physical address space larger than 4GB and happen to not enable sparsemem and include asm/sparsemem.h from asm/pgtable.h. After the initial discussion, I suggested just always defining MAX_POSSIBLE_PHYSMEM_BITS whenever CONFIG_PHYS_ADDR_T_64BIT is set, or provoking a build error otherwise. This addresses all configurations that can currently have this runtime bug, but leaves all other configurations unchanged. I looked up the possible number of bits in source code and datasheets, here is what I found: - on ARC, CONFIG_ARC_HAS_PAE40 controls whether 32 or 40 bits are used - on ARM, CONFIG_LPAE enables 40 bit addressing, without it we never support more than 32 bits, even though supersections in theory allow up to 40 bits as well. - on MIPS, some MIPS32r1 or later chips support 36 bits, and MIPS32r5 XPA supports up to 60 bits in theory, but 40 bits are more than anyone will ever ship - On PowerPC, there are three different implementations of 36 bit addressing, but 32-bit is used without CONFIG_PTE_64BIT - On RISC-V, the normal page table format can support 34 bit addressing. There is no highmem support on RISC-V, so anything above 2GB is unused, but it might be useful to eventually support CONFIG_ZRAM for high pages. Fixes: 61989a80fb3a ("staging: zsmalloc: zsmalloc memory allocation library") Fixes: 02390b87a945 ("mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS") Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Reviewed-by: Stefan Agner <stefan@agner.ch> Tested-by: Stefan Agner <stefan@agner.ch> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Link: https://lore.kernel.org/linux-mm/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@agner.ch/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Sasha Levin <sashal@kernel.org> [florian: patch arch/powerpc/include/asm/pte-common.h for 4.9.y removed arch/riscv/include/asm/pgtable.h which does not exist] Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- arch/arc/include/asm/pgtable.h | 2 ++ arch/arm/include/asm/pgtable-2level.h | 2 ++ arch/arm/include/asm/pgtable-3level.h | 2 ++ arch/mips/include/asm/pgtable-32.h | 3 +++ arch/powerpc/include/asm/pte-common.h | 2 ++ include/asm-generic/pgtable.h | 13 +++++++++++++ 6 files changed, 24 insertions(+) --- a/arch/arc/include/asm/pgtable.h +++ b/arch/arc/include/asm/pgtable.h @@ -137,8 +137,10 @@ #ifdef CONFIG_ARC_HAS_PAE40 #define PTE_BITS_NON_RWX_IN_PD1 (0xff00000000 | PAGE_MASK | _PAGE_CACHEABLE) +#define MAX_POSSIBLE_PHYSMEM_BITS 40 #else #define PTE_BITS_NON_RWX_IN_PD1 (PAGE_MASK | _PAGE_CACHEABLE) +#define MAX_POSSIBLE_PHYSMEM_BITS 32 #endif /************************************************************************** --- a/arch/arm/include/asm/pgtable-2level.h +++ b/arch/arm/include/asm/pgtable-2level.h @@ -78,6 +78,8 @@ #define PTE_HWTABLE_OFF (PTE_HWTABLE_PTRS * sizeof(pte_t)) #define PTE_HWTABLE_SIZE (PTRS_PER_PTE * sizeof(u32)) +#define MAX_POSSIBLE_PHYSMEM_BITS 32 + /* * PMD_SHIFT determines the size of the area a second-level page table can map * PGDIR_SHIFT determines what a third-level page table entry can map --- a/arch/arm/include/asm/pgtable-3level.h +++ b/arch/arm/include/asm/pgtable-3level.h @@ -37,6 +37,8 @@ #define PTE_HWTABLE_OFF (0) #define PTE_HWTABLE_SIZE (PTRS_PER_PTE * sizeof(u64)) +#define MAX_POSSIBLE_PHYSMEM_BITS 40 + /* * PGDIR_SHIFT determines the size a top-level page table entry can map. */ --- a/arch/mips/include/asm/pgtable-32.h +++ b/arch/mips/include/asm/pgtable-32.h @@ -110,6 +110,7 @@ static inline void pmd_clear(pmd_t *pmdp #if defined(CONFIG_XPA) +#define MAX_POSSIBLE_PHYSMEM_BITS 40 #define pte_pfn(x) (((unsigned long)((x).pte_high >> _PFN_SHIFT)) | (unsigned long)((x).pte_low << _PAGE_PRESENT_SHIFT)) static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) @@ -125,6 +126,7 @@ pfn_pte(unsigned long pfn, pgprot_t prot #elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) +#define MAX_POSSIBLE_PHYSMEM_BITS 36 #define pte_pfn(x) ((unsigned long)((x).pte_high >> 6)) static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) @@ -139,6 +141,7 @@ static inline pte_t pfn_pte(unsigned lon #else +#define MAX_POSSIBLE_PHYSMEM_BITS 32 #ifdef CONFIG_CPU_VR41XX #define pte_pfn(x) ((unsigned long)((x).pte >> (PAGE_SHIFT + 2))) #define pfn_pte(pfn, prot) __pte(((pfn) << (PAGE_SHIFT + 2)) | pgprot_val(prot)) --- a/arch/powerpc/include/asm/pte-common.h +++ b/arch/powerpc/include/asm/pte-common.h @@ -101,8 +101,10 @@ static inline bool pte_user(pte_t pte) */ #if defined(CONFIG_PPC32) && defined(CONFIG_PTE_64BIT) #define PTE_RPN_MASK (~((1ULL<<PTE_RPN_SHIFT)-1)) +#define MAX_POSSIBLE_PHYSMEM_BITS 36 #else #define PTE_RPN_MASK (~((1UL<<PTE_RPN_SHIFT)-1)) +#define MAX_POSSIBLE_PHYSMEM_BITS 32 #endif /* _PAGE_CHG_MASK masks of bits that are to be preserved across --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -847,6 +847,19 @@ static inline bool arch_has_pfn_modify_c #define io_remap_pfn_range remap_pfn_range #endif +#if !defined(MAX_POSSIBLE_PHYSMEM_BITS) && !defined(CONFIG_64BIT) +#ifdef CONFIG_PHYS_ADDR_T_64BIT +/* + * ZSMALLOC needs to know the highest PFN on 32-bit architectures + * with physical address space extension, but falls back to + * BITS_PER_LONG otherwise. + */ +#error Missing MAX_POSSIBLE_PHYSMEM_BITS definition +#else +#define MAX_POSSIBLE_PHYSMEM_BITS 32 +#endif +#endif + #ifndef has_transparent_hugepage #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define has_transparent_hugepage() 1 Patches currently in stable-queue which might be from f.fainelli@gmail.com are queue-4.9/mm-zsmalloc-prepare-to-variable-max_physmem_bits.patch queue-4.9/arch-pgtable-define-max_possible_physmem_bits-where-needed.patch ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-11-04 8:35 UTC | newest] Thread overview: 5+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2021-11-03 20:57 [PATCH stable 4.9 0/2] zsmalloc MAX_POSSIBLE_PHYSMEM_BITS Florian Fainelli 2021-11-03 20:57 ` [PATCH stable 4.9 1/2] mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS Florian Fainelli 2021-11-04 8:34 ` Patch "mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS" has been added to the 4.9-stable tree gregkh 2021-11-03 20:57 ` [PATCH stable 4.9 2/2] arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed Florian Fainelli 2021-11-04 8:34 ` Patch "arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed" has been added to the 4.9-stable tree gregkh
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