* [PATCH stable 4.14 0/2] zsmalloc MAX_POSSIBLE_PHYSMEM_BITS @ 2021-11-03 20:57 Florian Fainelli 2021-11-03 20:57 ` [PATCH stable 4.14 1/2] mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS Florian Fainelli 2021-11-03 20:57 ` [PATCH stable 4.14 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: stable, Greg Kroah-Hartman, Sasha Levin, Florian Fainelli, Vineet Gupta, Russell King, Ralf Baechle, Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, Thomas Gleixner, Ingo Molnar, H. Peter Anvin, maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT), Arnd Bergmann, Minchan Kim, Nitin Gupta, Sergey Senozhatsky, Stefan Agner, Thomas Bogendoerfer, Mike Rapoport, Kirill A. Shutemov, open list:SYNOPSYS ARC ARCHITECTURE, moderated list:ARM PORT, open list:MIPS, open list:LINUX FOR POWERPC (32-BIT AND 64-BIT), open list:GENERIC INCLUDE/ASM HEADER FILES, open list:ZSMALLOC COMPRESSED SLAB MEMORY ALLOCATOR 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 + arch/x86/include/asm/pgtable_64_types.h | 2 ++ include/asm-generic/pgtable.h | 13 +++++++++++++ mm/zsmalloc.c | 13 +++++++------ 9 files changed, 34 insertions(+), 6 deletions(-) -- 2.25.1 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH stable 4.14 1/2] mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS 2021-11-03 20:57 [PATCH stable 4.14 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 4.14-stable tree gregkh 2021-11-03 20:57 ` [PATCH stable 4.14 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: stable, Greg Kroah-Hartman, Sasha Levin, Kirill A. Shutemov, Nitin Gupta, Minchan Kim, Andy Lutomirski, Borislav Petkov, Linus Torvalds, Peter Zijlstra, Sergey Senozhatsky, Thomas Gleixner, linux-mm, Ingo Molnar, Florian Fainelli, Vineet Gupta, Russell King, Ralf Baechle, Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, Ingo Molnar, H. Peter Anvin, maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT), Arnd Bergmann, Stefan Agner, Thomas Bogendoerfer, Mike Rapoport, open list:SYNOPSYS ARC ARCHITECTURE, moderated list:ARM PORT, open list:MIPS, open list:LINUX FOR POWERPC (32-BIT AND 64-BIT), open list:GENERIC INCLUDE/ASM HEADER FILES 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> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> --- arch/x86/include/asm/pgtable-3level_types.h | 1 + arch/x86/include/asm/pgtable_64_types.h | 2 ++ mm/zsmalloc.c | 13 +++++++------ 3 files changed, 10 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/pgtable-3level_types.h b/arch/x86/include/asm/pgtable-3level_types.h index 876b4c77d983..6a59a6d0cc50 100644 --- a/arch/x86/include/asm/pgtable-3level_types.h +++ b/arch/x86/include/asm/pgtable-3level_types.h @@ -44,5 +44,6 @@ typedef union { */ #define PTRS_PER_PTE 512 +#define MAX_POSSIBLE_PHYSMEM_BITS 36 #endif /* _ASM_X86_PGTABLE_3LEVEL_DEFS_H */ diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index bf6d2692fc60..2bd79b7ae9d6 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -40,6 +40,8 @@ typedef struct { pteval_t pte; } pte_t; #define P4D_SIZE (_AC(1, UL) << P4D_SHIFT) #define P4D_MASK (~(P4D_SIZE - 1)) +#define MAX_POSSIBLE_PHYSMEM_BITS 52 + #else /* CONFIG_X86_5LEVEL */ /* diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 6ed736ea9b59..633ebcac82f8 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 4.14-stable tree 2021-11-03 20:57 ` [PATCH stable 4.14 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 4.14-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-4.14 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 09:33:05 AM CET 2021 From: Florian Fainelli <f.fainelli@gmail.com> Date: Wed, 3 Nov 2021 13:57:03 -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>, Stefan Agner <stefan@agn er.ch>, Thomas Bogendoerfer <tsbogend@alpha.franken.de>, Mike Rapoport <rppt@linux.ibm.com>, 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: <20211103205704.374734-2-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> 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 + arch/x86/include/asm/pgtable_64_types.h | 2 ++ mm/zsmalloc.c | 13 +++++++------ 3 files changed, 10 insertions(+), 6 deletions(-) --- a/arch/x86/include/asm/pgtable-3level_types.h +++ b/arch/x86/include/asm/pgtable-3level_types.h @@ -44,5 +44,6 @@ typedef union { */ #define PTRS_PER_PTE 512 +#define MAX_POSSIBLE_PHYSMEM_BITS 36 #endif /* _ASM_X86_PGTABLE_3LEVEL_DEFS_H */ --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -40,6 +40,8 @@ typedef struct { pteval_t pte; } pte_t; #define P4D_SIZE (_AC(1, UL) << P4D_SHIFT) #define P4D_MASK (~(P4D_SIZE - 1)) +#define MAX_POSSIBLE_PHYSMEM_BITS 52 + #else /* CONFIG_X86_5LEVEL */ /* --- 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-4.14/mm-zsmalloc-prepare-to-variable-max_physmem_bits.patch queue-4.14/arch-pgtable-define-max_possible_physmem_bits-where-needed.patch ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH stable 4.14 2/2] arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed 2021-11-03 20:57 [PATCH stable 4.14 0/2] zsmalloc MAX_POSSIBLE_PHYSMEM_BITS Florian Fainelli 2021-11-03 20:57 ` [PATCH stable 4.14 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 4.14-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: stable, Greg Kroah-Hartman, Sasha Levin, Arnd Bergmann, Thomas Bogendoerfer, Stefan Agner, Mike Rapoport, Florian Fainelli, Vineet Gupta, Russell King, Ralf Baechle, Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, Thomas Gleixner, Ingo Molnar, H. Peter Anvin, maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT), Minchan Kim, Nitin Gupta, Sergey Senozhatsky, Kirill A. Shutemov, open list:SYNOPSYS ARC ARCHITECTURE, moderated list:ARM PORT, open list:MIPS, open list:LINUX FOR POWERPC (32-BIT AND 64-BIT), open list:GENERIC INCLUDE/ASM HEADER FILES, open list:ZSMALLOC COMPRESSED SLAB MEMORY ALLOCATOR 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 4.14.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 77676e18da69..a31ae69da639 100644 --- a/arch/arc/include/asm/pgtable.h +++ b/arch/arc/include/asm/pgtable.h @@ -138,8 +138,10 @@ #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 74afe8c76bdd..215fb48f644b 100644 --- a/arch/mips/include/asm/pgtable-32.h +++ b/arch/mips/include/asm/pgtable-32.h @@ -111,6 +111,7 @@ 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) @@ -126,6 +127,7 @@ 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) @@ -140,6 +142,7 @@ 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 ce142ef99ba7..18ebe9a4728e 100644 --- a/arch/powerpc/include/asm/pte-common.h +++ b/arch/powerpc/include/asm/pte-common.h @@ -102,8 +102,10 @@ 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 cdee19314061..dd65e925f7cf 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -1069,6 +1069,19 @@ static inline bool arch_has_pfn_modify_check(void) #endif /* !__ASSEMBLY__ */ +#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 4.14-stable tree 2021-11-03 20:57 ` [PATCH stable 4.14 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 4.14-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-4.14 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 09:33:05 AM CET 2021 From: Florian Fainelli <f.fainelli@gmail.com> Date: Wed, 3 Nov 2021 13:57:04 -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: <20211103205704.374734-3-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 4.14.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 @@ -138,8 +138,10 @@ #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 @@ -111,6 +111,7 @@ 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) @@ -126,6 +127,7 @@ 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) @@ -140,6 +142,7 @@ 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 @@ -102,8 +102,10 @@ 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 @@ -1069,6 +1069,19 @@ static inline bool arch_has_pfn_modify_c #endif /* !__ASSEMBLY__ */ +#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-4.14/mm-zsmalloc-prepare-to-variable-max_physmem_bits.patch queue-4.14/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 4.14 0/2] zsmalloc MAX_POSSIBLE_PHYSMEM_BITS Florian Fainelli 2021-11-03 20:57 ` [PATCH stable 4.14 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 4.14-stable tree gregkh 2021-11-03 20:57 ` [PATCH stable 4.14 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 4.14-stable tree gregkh
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