From ef1a0722ee270886a434ebcabcb2fdeb1d7797f5 Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Wed, 16 Oct 2024 13:27:44 -0700 Subject: [PATCH 01/10] riscv: Add CSR definitions for pointer masking mainline inclusion from Linux 6.13-rc1 commit 29eedc7d1587f42f33ae209be45c89c424ee9c00 category: feature bugzilla: https://github.com/RVCK-Project/rvck/issues/335 -------------------------------- Pointer masking is controlled via a two-bit PMM field, which appears in various CSRs depending on which extensions are implemented. Smmpm adds the field to mseccfg; Smnpm adds the field to menvcfg; Ssnpm adds the field to senvcfg. If the H extension is implemented, Ssnpm also defines henvcfg.PMM and hstatus.HUPMM. Reviewed-by: Charlie Jenkins Signed-off-by: Samuel Holland Signed-off-by: Fangyu Yu --- arch/riscv/include/asm/csr.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h index 7791600b3964..c42a394363dd 100644 --- a/arch/riscv/include/asm/csr.h +++ b/arch/riscv/include/asm/csr.h @@ -138,6 +138,10 @@ /* HSTATUS flags */ #ifdef CONFIG_64BIT +#define HSTATUS_HUPMM _AC(0x3000000000000, UL) +#define HSTATUS_HUPMM_PMLEN_0 _AC(0x0000000000000, UL) +#define HSTATUS_HUPMM_PMLEN_7 _AC(0x2000000000000, UL) +#define HSTATUS_HUPMM_PMLEN_16 _AC(0x3000000000000, UL) #define HSTATUS_VSXL _AC(0x300000000, UL) #define HSTATUS_VSXL_SHIFT 32 #endif @@ -215,6 +219,10 @@ #define ENVCFG_STCE (_AC(1, ULL) << 63) #define ENVCFG_PBMTE (_AC(1, ULL) << 62) #define ENVCFG_ADUE (_AC(1, ULL) << 61) +#define ENVCFG_PMM (_AC(0x3, ULL) << 32) +#define ENVCFG_PMM_PMLEN_0 (_AC(0x0, ULL) << 32) +#define ENVCFG_PMM_PMLEN_7 (_AC(0x2, ULL) << 32) +#define ENVCFG_PMM_PMLEN_16 (_AC(0x3, ULL) << 32) #define ENVCFG_CBZE (_AC(1, UL) << 7) #define ENVCFG_CBCFE (_AC(1, UL) << 6) #define ENVCFG_LPE (_AC(1, UL) << 2) @@ -238,6 +246,12 @@ #define SMSTATEEN0_SSTATEEN0_SHIFT 63 #define SMSTATEEN0_SSTATEEN0 (_ULL(1) << SMSTATEEN0_SSTATEEN0_SHIFT) +/* mseccfg bits */ +#define MSECCFG_PMM ENVCFG_PMM +#define MSECCFG_PMM_PMLEN_0 ENVCFG_PMM_PMLEN_0 +#define MSECCFG_PMM_PMLEN_7 ENVCFG_PMM_PMLEN_7 +#define MSECCFG_PMM_PMLEN_16 ENVCFG_PMM_PMLEN_16 + /* symbolic CSR names: */ #define CSR_CYCLE 0xc00 #define CSR_TIME 0xc01 @@ -416,6 +430,8 @@ #define CSR_MIP 0x344 #define CSR_PMPCFG0 0x3a0 #define CSR_PMPADDR0 0x3b0 +#define CSR_MSECCFG 0x747 +#define CSR_MSECCFGH 0x757 #define CSR_MVENDORID 0xf11 #define CSR_MARCHID 0xf12 #define CSR_MIMPID 0xf13 From 2ea64f1a496c114f6991659d8dec11dc30604e4c Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Wed, 16 Oct 2024 13:27:45 -0700 Subject: [PATCH 02/10] riscv: Add support for userspace pointer masking mainline inclusion from Linux 6.13-rc1 commit 09d6775f503b393d0457c7126aa43208e1724004 category: feature bugzilla: https://github.com/RVCK-Project/rvck/issues/335 -------------------------------- RISC-V supports pointer masking with a variable number of tag bits (which is called "PMLEN" in the specification) and which is configured at the next higher privilege level. Wire up the PR_SET_TAGGED_ADDR_CTRL and PR_GET_TAGGED_ADDR_CTRL prctls so userspace can request a lower bound on the number of tag bits and determine the actual number of tag bits. As with arm64's PR_TAGGED_ADDR_ENABLE, the pointer masking configuration is thread-scoped, inherited on clone() and fork() and cleared on execve(). Reviewed-by: Charlie Jenkins Tested-by: Charlie Jenkins Signed-off-by: Samuel Holland Signed-off-by: Fangyu Yu --- Documentation/arch/riscv/uabi.rst | 12 ++++ arch/riscv/Kconfig | 11 ++++ arch/riscv/include/asm/processor.h | 8 +++ arch/riscv/include/asm/switch_to.h | 11 ++++ arch/riscv/kernel/process.c | 91 ++++++++++++++++++++++++++++++ include/uapi/linux/prctl.h | 5 +- 6 files changed, 137 insertions(+), 1 deletion(-) diff --git a/Documentation/arch/riscv/uabi.rst b/Documentation/arch/riscv/uabi.rst index 54d199dce78b..9c93dc2ebcf5 100644 --- a/Documentation/arch/riscv/uabi.rst +++ b/Documentation/arch/riscv/uabi.rst @@ -66,3 +66,15 @@ Misaligned accesses ------------------- Misaligned accesses are supported in userspace, but they may perform poorly. + +Pointer masking +--------------- + +Support for pointer masking in userspace (the Supm extension) is provided via +the ``PR_SET_TAGGED_ADDR_CTRL`` and ``PR_GET_TAGGED_ADDR_CTRL`` ``prctl()`` +operations. Pointer masking is disabled by default. To enable it, userspace +must call ``PR_SET_TAGGED_ADDR_CTRL`` with the ``PR_PMLEN`` field set to the +number of mask/tag bits needed by the application. ``PR_PMLEN`` is interpreted +as a lower bound; if the kernel is unable to satisfy the request, the +``PR_SET_TAGGED_ADDR_CTRL`` operation will fail. The actual number of tag bits +is returned in ``PR_PMLEN`` by the ``PR_GET_TAGGED_ADDR_CTRL`` operation. diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 6d981f7da79a..817a60a1816e 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -541,6 +541,17 @@ config RISCV_ISA_C If you don't know what to do here, say Y. +config RISCV_ISA_SUPM + bool "Supm extension for userspace pointer masking" + depends on 64BIT + default y + help + Add support for pointer masking in userspace (Supm) when the + underlying hardware extension (Smnpm or Ssnpm) is detected at boot. + + If this option is disabled, userspace will be unable to use + the prctl(PR_{SET,GET}_TAGGED_ADDR_CTRL) API. + config RISCV_ISA_SVNAPOT bool "Svnapot extension support for supervisor mode NAPOT pages" depends on 64BIT && MMU diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h index 44ddcdb97994..b7ce879d3f79 100644 --- a/arch/riscv/include/asm/processor.h +++ b/arch/riscv/include/asm/processor.h @@ -192,6 +192,14 @@ extern int set_unalign_ctl(struct task_struct *tsk, unsigned int val); #define GET_UNALIGN_CTL(tsk, addr) get_unalign_ctl((tsk), (addr)) #define SET_UNALIGN_CTL(tsk, val) set_unalign_ctl((tsk), (val)) +#ifdef CONFIG_RISCV_ISA_SUPM +/* PR_{SET,GET}_TAGGED_ADDR_CTRL prctl */ +long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg); +long get_tagged_addr_ctrl(struct task_struct *task); +#define SET_TAGGED_ADDR_CTRL(arg) set_tagged_addr_ctrl(current, arg) +#define GET_TAGGED_ADDR_CTRL() get_tagged_addr_ctrl(current) +#endif + #endif /* __ASSEMBLY__ */ #endif /* _ASM_RISCV_PROCESSOR_H */ diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h index 6134e302686f..20e6fffb0974 100644 --- a/arch/riscv/include/asm/switch_to.h +++ b/arch/riscv/include/asm/switch_to.h @@ -84,6 +84,17 @@ static __always_inline bool has_fpu(void) { return false; } #define __switch_to_fpu(__prev, __next) do { } while (0) #endif +static inline void envcfg_update_bits(struct task_struct *task, + unsigned long mask, unsigned long val) +{ + unsigned long envcfg; + + envcfg = (task->thread.envcfg & ~mask) | val; + task->thread.envcfg = envcfg; + if (task == current) + csr_write(CSR_ENVCFG, envcfg); +} + static inline void __switch_to_envcfg(struct task_struct *next) { asm volatile (ALTERNATIVE("nop", "csrw " __stringify(CSR_ENVCFG) ", %0", diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index e734f1c0358c..7db81e883d95 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -7,6 +7,7 @@ * Copyright (C) 2017 SiFive */ +#include #include #include #include @@ -191,6 +192,10 @@ void flush_thread(void) memset(¤t->thread.vstate, 0, sizeof(struct __riscv_v_ext_state)); clear_tsk_thread_flag(current, TIF_RISCV_V_DEFER_RESTORE); #endif +#ifdef CONFIG_RISCV_ISA_SUPM + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SUPM)) + envcfg_update_bits(current, ENVCFG_PMM, ENVCFG_PMM_PMLEN_0); +#endif } void arch_release_task_struct(struct task_struct *tsk) @@ -275,5 +280,91 @@ void __init arch_task_cache_init(void) riscv_v_setup_ctx_cache(); } +#ifdef CONFIG_RISCV_ISA_SUPM +enum { + PMLEN_0 = 0, + PMLEN_7 = 7, + PMLEN_16 = 16, +}; + +static bool have_user_pmlen_7; +static bool have_user_pmlen_16; + +long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg) +{ + unsigned long valid_mask = PR_PMLEN_MASK; + struct thread_info *ti = task_thread_info(task); + unsigned long pmm; + u8 pmlen; + + if (is_compat_thread(ti)) + return -EINVAL; + + if (arg & ~valid_mask) + return -EINVAL; + + /* + * Prefer the smallest PMLEN that satisfies the user's request, + * in case choosing a larger PMLEN has a performance impact. + */ + pmlen = FIELD_GET(PR_PMLEN_MASK, arg); + if (pmlen == PMLEN_0) + pmm = ENVCFG_PMM_PMLEN_0; + else if (pmlen <= PMLEN_7 && have_user_pmlen_7) + pmm = ENVCFG_PMM_PMLEN_7; + else if (pmlen <= PMLEN_16 && have_user_pmlen_16) + pmm = ENVCFG_PMM_PMLEN_16; + else + return -EINVAL; + + envcfg_update_bits(task, ENVCFG_PMM, pmm); + + return 0; +} + +long get_tagged_addr_ctrl(struct task_struct *task) +{ + struct thread_info *ti = task_thread_info(task); + long ret = 0; + + if (is_compat_thread(ti)) + return -EINVAL; + + switch (task->thread.envcfg & ENVCFG_PMM) { + case ENVCFG_PMM_PMLEN_7: + ret = FIELD_PREP(PR_PMLEN_MASK, PMLEN_7); + break; + case ENVCFG_PMM_PMLEN_16: + ret = FIELD_PREP(PR_PMLEN_MASK, PMLEN_16); + break; + } + + return ret; +} + +static bool try_to_set_pmm(unsigned long value) +{ + csr_set(CSR_ENVCFG, value); + return (csr_read_clear(CSR_ENVCFG, ENVCFG_PMM) & ENVCFG_PMM) == value; +} + +static int __init tagged_addr_init(void) +{ + if (!riscv_has_extension_unlikely(RISCV_ISA_EXT_SUPM)) + return 0; + + /* + * envcfg.PMM is a WARL field. Detect which values are supported. + * Assume the supported PMLEN values are the same on all harts. + */ + csr_clear(CSR_ENVCFG, ENVCFG_PMM); + have_user_pmlen_7 = try_to_set_pmm(ENVCFG_PMM_PMLEN_7); + have_user_pmlen_16 = try_to_set_pmm(ENVCFG_PMM_PMLEN_16); + + return 0; +} +core_initcall(tagged_addr_init); +#endif /* CONFIG_RISCV_ISA_SUPM */ + EXPORT_SYMBOL_GPL(__fstate_save); EXPORT_SYMBOL_GPL(__fstate_restore); diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index 906a46c4be4f..5cb1eca190ef 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -230,7 +230,7 @@ struct prctl_mm_map { # define PR_PAC_APDBKEY (1UL << 3) # define PR_PAC_APGAKEY (1UL << 4) -/* Tagged user address controls for arm64 */ +/* Tagged user address controls for arm64 and RISC-V */ #define PR_SET_TAGGED_ADDR_CTRL 55 #define PR_GET_TAGGED_ADDR_CTRL 56 # define PR_TAGGED_ADDR_ENABLE (1UL << 0) @@ -244,6 +244,9 @@ struct prctl_mm_map { # define PR_MTE_TAG_MASK (0xffffUL << PR_MTE_TAG_SHIFT) /* Unused; kept only for source compatibility */ # define PR_MTE_TCF_SHIFT 1 +/* RISC-V pointer masking tag length */ +# define PR_PMLEN_SHIFT 24 +# define PR_PMLEN_MASK (0x7fUL << PR_PMLEN_SHIFT) /* Control reclaim behavior when allocating memory */ #define PR_SET_IO_FLUSHER 57 From 6f360dcfbdc7ec5a490faaa03158ab3972941c9c Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Wed, 16 Oct 2024 13:27:46 -0700 Subject: [PATCH 03/10] riscv: Add support for the tagged address ABI mainline inclusion from Linux 6.13-rc1 commit 2e1743085887ba3f553c2bb472a75a3ff744b242 category: feature bugzilla: https://github.com/RVCK-Project/rvck/issues/335 -------------------------------- When pointer masking is enabled for userspace, the kernel can accept tagged pointers as arguments to some system calls. Allow this by untagging the pointers in access_ok() and the uaccess routines. The uaccess routines must peform untagging in software because U-mode and S-mode have entirely separate pointer masking configurations. In fact, hardware may not even implement pointer masking for S-mode. Since the number of tag bits is variable, untagged_addr_remote() needs to know what PMLEN to use for the remote mm. Therefore, the pointer masking mode must be the same for all threads sharing an mm. Enforce this with a lock flag in the mm context, as x86 does for LAM. The flag gets reset in init_new_context() during fork(), as the new mm is no longer multithreaded. Reviewed-by: Charlie Jenkins Tested-by: Charlie Jenkins Signed-off-by: Samuel Holland Signed-off-by: Fangyu Yu --- Documentation/arch/riscv/uabi.rst | 4 ++ arch/riscv/include/asm/mmu.h | 7 +++ arch/riscv/include/asm/mmu_context.h | 5 ++ arch/riscv/include/asm/uaccess.h | 43 ++++++++++++++-- arch/riscv/kernel/process.c | 73 ++++++++++++++++++++++++++-- 5 files changed, 122 insertions(+), 10 deletions(-) diff --git a/Documentation/arch/riscv/uabi.rst b/Documentation/arch/riscv/uabi.rst index 9c93dc2ebcf5..be6fbb395d56 100644 --- a/Documentation/arch/riscv/uabi.rst +++ b/Documentation/arch/riscv/uabi.rst @@ -78,3 +78,7 @@ number of mask/tag bits needed by the application. ``PR_PMLEN`` is interpreted as a lower bound; if the kernel is unable to satisfy the request, the ``PR_SET_TAGGED_ADDR_CTRL`` operation will fail. The actual number of tag bits is returned in ``PR_PMLEN`` by the ``PR_GET_TAGGED_ADDR_CTRL`` operation. + +Additionally, when pointer masking is enabled (``PR_PMLEN`` is greater than 0), +a tagged address ABI is supported, with the same interface and behavior as +documented for AArch64 (Documentation/arch/arm64/tagged-address-abi.rst). diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h index 6beca1d3f0e2..ba911fea92d1 100644 --- a/arch/riscv/include/asm/mmu.h +++ b/arch/riscv/include/asm/mmu.h @@ -23,9 +23,16 @@ typedef struct { #ifdef CONFIG_BINFMT_ELF_FDPIC unsigned long exec_fdpic_loadmap; unsigned long interp_fdpic_loadmap; +#endif + unsigned long flags; +#ifdef CONFIG_RISCV_ISA_SUPM + u8 pmlen; #endif } mm_context_t; +/* Lock the pointer masking mode because this mm is multithreaded */ +#define MM_CONTEXT_LOCK_PMLEN 0 + void __meminit create_pgd_mapping(pgd_t *pgdp, uintptr_t va, phys_addr_t pa, phys_addr_t sz, pgprot_t prot); #endif /* __ASSEMBLY__ */ diff --git a/arch/riscv/include/asm/mmu_context.h b/arch/riscv/include/asm/mmu_context.h index c71c48ee5431..dbf27a78df6c 100644 --- a/arch/riscv/include/asm/mmu_context.h +++ b/arch/riscv/include/asm/mmu_context.h @@ -20,6 +20,9 @@ void switch_mm(struct mm_struct *prev, struct mm_struct *next, static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next) { +#ifdef CONFIG_RISCV_ISA_SUPM + next->context.pmlen = 0; +#endif switch_mm(prev, next, NULL); } @@ -30,6 +33,8 @@ static inline int init_new_context(struct task_struct *tsk, #ifdef CONFIG_MMU atomic_long_set(&mm->context.id, 0); #endif + if (IS_ENABLED(CONFIG_RISCV_ISA_SUPM)) + clear_bit(MM_CONTEXT_LOCK_PMLEN, &mm->context.flags); return 0; } diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h index af74dcdbe4f9..f5f4f7f85543 100644 --- a/arch/riscv/include/asm/uaccess.h +++ b/arch/riscv/include/asm/uaccess.h @@ -9,8 +9,41 @@ #define _ASM_RISCV_UACCESS_H #include +#include #include /* for TASK_SIZE */ +#ifdef CONFIG_RISCV_ISA_SUPM +static inline unsigned long __untagged_addr_remote(struct mm_struct *mm, unsigned long addr) +{ + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SUPM)) { + u8 pmlen = mm->context.pmlen; + + /* Virtual addresses are sign-extended; physical addresses are zero-extended. */ + if (IS_ENABLED(CONFIG_MMU)) + return (long)(addr << pmlen) >> pmlen; + else + return (addr << pmlen) >> pmlen; + } + + return addr; +} + +#define untagged_addr(addr) ({ \ + unsigned long __addr = (__force unsigned long)(addr); \ + (__force __typeof__(addr))__untagged_addr_remote(current->mm, __addr); \ +}) + +#define untagged_addr_remote(mm, addr) ({ \ + unsigned long __addr = (__force unsigned long)(addr); \ + mmap_assert_locked(mm); \ + (__force __typeof__(addr))__untagged_addr_remote(mm, __addr); \ +}) + +#define access_ok(addr, size) likely(__access_ok(untagged_addr(addr), size)) +#else +#define untagged_addr(addr) (addr) +#endif + /* * User space memory access functions */ @@ -202,7 +235,7 @@ __gu_failed: \ */ #define __get_user(x, ptr) \ ({ \ - const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \ + const __typeof__(*(ptr)) __user *__gu_ptr = untagged_addr(ptr); \ long __gu_err = 0; \ __typeof__(x) __gu_val; \ \ @@ -333,7 +366,7 @@ err_label: \ */ #define __put_user(x, ptr) \ ({ \ - __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \ + __typeof__(*(ptr)) __user *__gu_ptr = untagged_addr(ptr); \ __typeof__(*__gu_ptr) __val = (x); \ long __pu_err = 0; \ \ @@ -380,13 +413,13 @@ unsigned long __must_check __asm_copy_from_user(void *to, static inline unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n) { - return __asm_copy_from_user(to, from, n); + return __asm_copy_from_user(to, untagged_addr(from), n); } static inline unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n) { - return __asm_copy_to_user(to, from, n); + return __asm_copy_to_user(untagged_addr(to), from, n); } extern long strncpy_from_user(char *dest, const char __user *src, long count); @@ -401,7 +434,7 @@ unsigned long __must_check clear_user(void __user *to, unsigned long n) { might_fault(); return access_ok(to, n) ? - __clear_user(to, n) : n; + __clear_user(untagged_addr(to), n) : n; } #define __get_kernel_nofault(dst, src, type, err_label) \ diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index 7db81e883d95..2574c783c4b8 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -237,6 +237,10 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) unsigned long ssp = 0; struct pt_regs *childregs = task_pt_regs(p); + /* Ensure all threads in this mm have the same pointer masking mode. */ + if (IS_ENABLED(CONFIG_RISCV_ISA_SUPM) && p->mm && (clone_flags & CLONE_VM)) + set_bit(MM_CONTEXT_LOCK_PMLEN, &p->mm->context.flags); + memset(&p->thread.s, 0, sizeof(p->thread.s)); /* p->thread holds context to be restored by __switch_to() */ @@ -290,10 +294,16 @@ enum { static bool have_user_pmlen_7; static bool have_user_pmlen_16; +/* + * Control the relaxed ABI allowing tagged user addresses into the kernel. + */ +static unsigned int tagged_addr_disabled; + long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg) { - unsigned long valid_mask = PR_PMLEN_MASK; + unsigned long valid_mask = PR_PMLEN_MASK | PR_TAGGED_ADDR_ENABLE; struct thread_info *ti = task_thread_info(task); + struct mm_struct *mm = task->mm; unsigned long pmm; u8 pmlen; @@ -308,16 +318,41 @@ long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg) * in case choosing a larger PMLEN has a performance impact. */ pmlen = FIELD_GET(PR_PMLEN_MASK, arg); - if (pmlen == PMLEN_0) + if (pmlen == PMLEN_0) { pmm = ENVCFG_PMM_PMLEN_0; - else if (pmlen <= PMLEN_7 && have_user_pmlen_7) + } else if (pmlen <= PMLEN_7 && have_user_pmlen_7) { + pmlen = PMLEN_7; pmm = ENVCFG_PMM_PMLEN_7; - else if (pmlen <= PMLEN_16 && have_user_pmlen_16) + } else if (pmlen <= PMLEN_16 && have_user_pmlen_16) { + pmlen = PMLEN_16; pmm = ENVCFG_PMM_PMLEN_16; - else + } else { return -EINVAL; + } + + /* + * Do not allow the enabling of the tagged address ABI if globally + * disabled via sysctl abi.tagged_addr_disabled, if pointer masking + * is disabled for userspace. + */ + if (arg & PR_TAGGED_ADDR_ENABLE && (tagged_addr_disabled || !pmlen)) + return -EINVAL; + + if (!(arg & PR_TAGGED_ADDR_ENABLE)) + pmlen = PMLEN_0; + + if (mmap_write_lock_killable(mm)) + return -EINTR; + + if (test_bit(MM_CONTEXT_LOCK_PMLEN, &mm->context.flags) && mm->context.pmlen != pmlen) { + mmap_write_unlock(mm); + return -EBUSY; + } envcfg_update_bits(task, ENVCFG_PMM, pmm); + mm->context.pmlen = pmlen; + + mmap_write_unlock(mm); return 0; } @@ -330,6 +365,10 @@ long get_tagged_addr_ctrl(struct task_struct *task) if (is_compat_thread(ti)) return -EINVAL; + /* + * The mm context's pmlen is set only when the tagged address ABI is + * enabled, so the effective PMLEN must be extracted from envcfg.PMM. + */ switch (task->thread.envcfg & ENVCFG_PMM) { case ENVCFG_PMM_PMLEN_7: ret = FIELD_PREP(PR_PMLEN_MASK, PMLEN_7); @@ -339,6 +378,9 @@ long get_tagged_addr_ctrl(struct task_struct *task) break; } + if (task->mm->context.pmlen) + ret |= PR_TAGGED_ADDR_ENABLE; + return ret; } @@ -348,6 +390,24 @@ static bool try_to_set_pmm(unsigned long value) return (csr_read_clear(CSR_ENVCFG, ENVCFG_PMM) & ENVCFG_PMM) == value; } +/* + * Global sysctl to disable the tagged user addresses support. This control + * only prevents the tagged address ABI enabling via prctl() and does not + * disable it for tasks that already opted in to the relaxed ABI. + */ + +static struct ctl_table tagged_addr_sysctl_table[] = { + { + .procname = "tagged_addr_disabled", + .mode = 0644, + .data = &tagged_addr_disabled, + .maxlen = sizeof(int), + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, +}; + static int __init tagged_addr_init(void) { if (!riscv_has_extension_unlikely(RISCV_ISA_EXT_SUPM)) @@ -361,6 +421,9 @@ static int __init tagged_addr_init(void) have_user_pmlen_7 = try_to_set_pmm(ENVCFG_PMM_PMLEN_7); have_user_pmlen_16 = try_to_set_pmm(ENVCFG_PMM_PMLEN_16); + if (!register_sysctl("abi", tagged_addr_sysctl_table)) + return -EINVAL; + return 0; } core_initcall(tagged_addr_init); From 9710058d81f2a1843fa7f07736ca4f0510415304 Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Wed, 16 Oct 2024 13:27:47 -0700 Subject: [PATCH 04/10] riscv: Allow ptrace control of the tagged address ABI mainline inclusion from Linux 6.13-rc1 commit 78844482a1c939a972681842f8ee2a8ddb202441 category: feature bugzilla: https://github.com/RVCK-Project/rvck/issues/335 -------------------------------- This allows a tracer to control the ABI of the tracee, as on arm64. Signed-off-by: Samuel Holland Signed-off-by: Fangyu Yu --- arch/riscv/kernel/ptrace.c | 42 ++++++++++++++++++++++++++++++++++++++ include/uapi/linux/elf.h | 1 + 2 files changed, 43 insertions(+) diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c index 5087d3a1dce8..998147b7be5c 100644 --- a/arch/riscv/kernel/ptrace.c +++ b/arch/riscv/kernel/ptrace.c @@ -29,6 +29,9 @@ enum riscv_regset { #ifdef CONFIG_RISCV_ISA_V REGSET_V, #endif +#ifdef CONFIG_RISCV_ISA_SUPM + REGSET_TAGGED_ADDR_CTRL, +#endif #ifdef CONFIG_RISCV_USER_CFI REGSET_CFI, #endif @@ -237,6 +240,35 @@ static int riscv_cfi_set(struct task_struct *target, } #endif +#ifdef CONFIG_RISCV_ISA_SUPM +static int tagged_addr_ctrl_get(struct task_struct *target, + const struct user_regset *regset, + struct membuf to) +{ + long ctrl = get_tagged_addr_ctrl(target); + + if (IS_ERR_VALUE(ctrl)) + return ctrl; + + return membuf_write(&to, &ctrl, sizeof(ctrl)); +} + +static int tagged_addr_ctrl_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + int ret; + long ctrl; + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl, 0, -1); + if (ret) + return ret; + + return set_tagged_addr_ctrl(target, ctrl); +} +#endif + static const struct user_regset riscv_user_regset[] = { [REGSET_X] = { .core_note_type = NT_PRSTATUS, @@ -267,6 +299,16 @@ static const struct user_regset riscv_user_regset[] = { .set = riscv_vr_set, }, #endif +#ifdef CONFIG_RISCV_ISA_SUPM + [REGSET_TAGGED_ADDR_CTRL] = { + .core_note_type = NT_RISCV_TAGGED_ADDR_CTRL, + .n = 1, + .size = sizeof(long), + .align = sizeof(long), + .regset_get = tagged_addr_ctrl_get, + .set = tagged_addr_ctrl_set, + }, +#endif #ifdef CONFIG_RISCV_USER_CFI [REGSET_CFI] = { .core_note_type = NT_RISCV_USER_CFI, diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h index 6b4c44ace911..1dd4240fd60d 100644 --- a/include/uapi/linux/elf.h +++ b/include/uapi/linux/elf.h @@ -447,6 +447,7 @@ typedef struct elf64_shdr { #define NT_MIPS_MSA 0x802 /* MIPS SIMD registers */ #define NT_RISCV_CSR 0x900 /* RISC-V Control and Status Registers */ #define NT_RISCV_VECTOR 0x901 /* RISC-V vector registers */ +#define NT_RISCV_TAGGED_ADDR_CTRL 0x902 /* RISC-V tagged address control (prctl()) */ #define NN_RISCV_USER_CFI "LINUX" #define NT_RISCV_USER_CFI 0x903 /* RISC-V shadow stack state */ #define NT_LOONGARCH_CPUCFG 0xa00 /* LoongArch CPU config registers */ From b7ca5853ad3e9084071d42bd32b2d25c2f708aa7 Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Wed, 16 Oct 2024 13:27:48 -0700 Subject: [PATCH 05/10] riscv: selftests: Add a pointer masking test mainline inclusion from Linux 6.13-rc1 commit 7470b5afd150e683c7aef03961d0c4c6f500de3b category: feature bugzilla: https://github.com/RVCK-Project/rvck/issues/335 -------------------------------- This test covers the behavior of the PR_SET_TAGGED_ADDR_CTRL and PR_GET_TAGGED_ADDR_CTRL prctl() operations, their effects on the userspace ABI, and their effects on the system call ABI. Reviewed-by: Charlie Jenkins Tested-by: Charlie Jenkins Signed-off-by: Samuel Holland Signed-off-by: Fangyu Yu --- tools/testing/selftests/riscv/Makefile | 2 +- tools/testing/selftests/riscv/abi/.gitignore | 1 + tools/testing/selftests/riscv/abi/Makefile | 10 + .../selftests/riscv/abi/pointer_masking.c | 332 ++++++++++++++++++ 4 files changed, 344 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/riscv/abi/.gitignore create mode 100644 tools/testing/selftests/riscv/abi/Makefile create mode 100644 tools/testing/selftests/riscv/abi/pointer_masking.c diff --git a/tools/testing/selftests/riscv/Makefile b/tools/testing/selftests/riscv/Makefile index 5976a0adec76..64a3c9c72622 100644 --- a/tools/testing/selftests/riscv/Makefile +++ b/tools/testing/selftests/riscv/Makefile @@ -5,7 +5,7 @@ ARCH ?= $(shell uname -m 2>/dev/null || echo not) ifneq (,$(filter $(ARCH),riscv)) -RISCV_SUBTARGETS ?= hwprobe vector mm sse cfi +RISCV_SUBTARGETS ?= abi hwprobe vector mm sse cfi else RISCV_SUBTARGETS := endif diff --git a/tools/testing/selftests/riscv/abi/.gitignore b/tools/testing/selftests/riscv/abi/.gitignore new file mode 100644 index 000000000000..b38358f91c4d --- /dev/null +++ b/tools/testing/selftests/riscv/abi/.gitignore @@ -0,0 +1 @@ +pointer_masking diff --git a/tools/testing/selftests/riscv/abi/Makefile b/tools/testing/selftests/riscv/abi/Makefile new file mode 100644 index 000000000000..ed82ff9c664e --- /dev/null +++ b/tools/testing/selftests/riscv/abi/Makefile @@ -0,0 +1,10 @@ +# SPDX-License-Identifier: GPL-2.0 + +CFLAGS += -I$(top_srcdir)/tools/include + +TEST_GEN_PROGS := pointer_masking + +include ../../lib.mk + +$(OUTPUT)/pointer_masking: pointer_masking.c + $(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^ diff --git a/tools/testing/selftests/riscv/abi/pointer_masking.c b/tools/testing/selftests/riscv/abi/pointer_masking.c new file mode 100644 index 000000000000..dee41b7ee3e3 --- /dev/null +++ b/tools/testing/selftests/riscv/abi/pointer_masking.c @@ -0,0 +1,332 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../../kselftest.h" + +#ifndef PR_PMLEN_SHIFT +#define PR_PMLEN_SHIFT 24 +#endif +#ifndef PR_PMLEN_MASK +#define PR_PMLEN_MASK (0x7fUL << PR_PMLEN_SHIFT) +#endif + +static int dev_zero; + +static int pipefd[2]; + +static sigjmp_buf jmpbuf; + +static void sigsegv_handler(int sig) +{ + siglongjmp(jmpbuf, 1); +} + +static int min_pmlen; +static int max_pmlen; + +static inline bool valid_pmlen(int pmlen) +{ + return pmlen == 0 || pmlen == 7 || pmlen == 16; +} + +static void test_pmlen(void) +{ + ksft_print_msg("Testing available PMLEN values\n"); + + for (int request = 0; request <= 16; request++) { + int pmlen, ret; + + ret = prctl(PR_SET_TAGGED_ADDR_CTRL, request << PR_PMLEN_SHIFT, 0, 0, 0); + if (ret) + goto pr_set_error; + + ret = prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0); + ksft_test_result(ret >= 0, "PMLEN=%d PR_GET_TAGGED_ADDR_CTRL\n", request); + if (ret < 0) + goto pr_get_error; + + pmlen = (ret & PR_PMLEN_MASK) >> PR_PMLEN_SHIFT; + ksft_test_result(pmlen >= request, "PMLEN=%d constraint\n", request); + ksft_test_result(valid_pmlen(pmlen), "PMLEN=%d validity\n", request); + + if (min_pmlen == 0) + min_pmlen = pmlen; + if (max_pmlen < pmlen) + max_pmlen = pmlen; + + continue; + +pr_set_error: + ksft_test_result_skip("PMLEN=%d PR_GET_TAGGED_ADDR_CTRL\n", request); +pr_get_error: + ksft_test_result_skip("PMLEN=%d constraint\n", request); + ksft_test_result_skip("PMLEN=%d validity\n", request); + } + + if (max_pmlen == 0) + ksft_exit_fail_msg("Failed to enable pointer masking\n"); +} + +static int set_tagged_addr_ctrl(int pmlen, bool tagged_addr_abi) +{ + int arg, ret; + + arg = pmlen << PR_PMLEN_SHIFT | tagged_addr_abi; + ret = prctl(PR_SET_TAGGED_ADDR_CTRL, arg, 0, 0, 0); + if (!ret) { + ret = prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0); + if (ret == arg) + return 0; + } + + return ret < 0 ? -errno : -ENODATA; +} + +static void test_dereference_pmlen(int pmlen) +{ + static volatile int i; + volatile int *p; + int ret; + + ret = set_tagged_addr_ctrl(pmlen, false); + if (ret) + return ksft_test_result_error("PMLEN=%d setup (%d)\n", pmlen, ret); + + i = pmlen; + + if (pmlen) { + p = (volatile int *)((uintptr_t)&i | 1UL << (__riscv_xlen - pmlen)); + + /* These dereferences should succeed. */ + if (sigsetjmp(jmpbuf, 1)) + return ksft_test_result_fail("PMLEN=%d valid tag\n", pmlen); + if (*p != pmlen) + return ksft_test_result_fail("PMLEN=%d bad value\n", pmlen); + ++*p; + } + + p = (volatile int *)((uintptr_t)&i | 1UL << (__riscv_xlen - pmlen - 1)); + + /* These dereferences should raise SIGSEGV. */ + if (sigsetjmp(jmpbuf, 1)) + return ksft_test_result_pass("PMLEN=%d dereference\n", pmlen); + ++*p; + ksft_test_result_fail("PMLEN=%d invalid tag\n", pmlen); +} + +static void test_dereference(void) +{ + ksft_print_msg("Testing userspace pointer dereference\n"); + + signal(SIGSEGV, sigsegv_handler); + + test_dereference_pmlen(0); + test_dereference_pmlen(min_pmlen); + test_dereference_pmlen(max_pmlen); + + signal(SIGSEGV, SIG_DFL); +} + +static void execve_child_sigsegv_handler(int sig) +{ + exit(42); +} + +static int execve_child(void) +{ + static volatile int i; + volatile int *p = (volatile int *)((uintptr_t)&i | 1UL << (__riscv_xlen - 7)); + + signal(SIGSEGV, execve_child_sigsegv_handler); + + /* This dereference should raise SIGSEGV. */ + return *p; +} + +static void test_fork_exec(void) +{ + int ret, status; + + ksft_print_msg("Testing fork/exec behavior\n"); + + ret = set_tagged_addr_ctrl(min_pmlen, false); + if (ret) + return ksft_test_result_error("setup (%d)\n", ret); + + if (fork()) { + wait(&status); + ksft_test_result(WIFEXITED(status) && WEXITSTATUS(status) == 42, + "dereference after fork\n"); + } else { + static volatile int i = 42; + volatile int *p; + + p = (volatile int *)((uintptr_t)&i | 1UL << (__riscv_xlen - min_pmlen)); + + /* This dereference should succeed. */ + exit(*p); + } + + if (fork()) { + wait(&status); + ksft_test_result(WIFEXITED(status) && WEXITSTATUS(status) == 42, + "dereference after fork+exec\n"); + } else { + /* Will call execve_child(). */ + execve("/proc/self/exe", (char *const []) { "", NULL }, NULL); + } +} + +static void test_tagged_addr_abi_sysctl(void) +{ + char value; + int fd; + + ksft_print_msg("Testing tagged address ABI sysctl\n"); + + fd = open("/proc/sys/abi/tagged_addr_disabled", O_WRONLY); + if (fd < 0) { + ksft_test_result_skip("failed to open sysctl file\n"); + ksft_test_result_skip("failed to open sysctl file\n"); + return; + } + + value = '1'; + pwrite(fd, &value, 1, 0); + ksft_test_result(set_tagged_addr_ctrl(min_pmlen, true) == -EINVAL, + "sysctl disabled\n"); + + value = '0'; + pwrite(fd, &value, 1, 0); + ksft_test_result(set_tagged_addr_ctrl(min_pmlen, true) == 0, + "sysctl enabled\n"); + + set_tagged_addr_ctrl(0, false); + + close(fd); +} + +static void test_tagged_addr_abi_pmlen(int pmlen) +{ + int i, *p, ret; + + i = ~pmlen; + + if (pmlen) { + p = (int *)((uintptr_t)&i | 1UL << (__riscv_xlen - pmlen)); + + ret = set_tagged_addr_ctrl(pmlen, false); + if (ret) + return ksft_test_result_error("PMLEN=%d ABI disabled setup (%d)\n", + pmlen, ret); + + ret = write(pipefd[1], p, sizeof(*p)); + if (ret >= 0 || errno != EFAULT) + return ksft_test_result_fail("PMLEN=%d ABI disabled write\n", pmlen); + + ret = read(dev_zero, p, sizeof(*p)); + if (ret >= 0 || errno != EFAULT) + return ksft_test_result_fail("PMLEN=%d ABI disabled read\n", pmlen); + + if (i != ~pmlen) + return ksft_test_result_fail("PMLEN=%d ABI disabled value\n", pmlen); + + ret = set_tagged_addr_ctrl(pmlen, true); + if (ret) + return ksft_test_result_error("PMLEN=%d ABI enabled setup (%d)\n", + pmlen, ret); + + ret = write(pipefd[1], p, sizeof(*p)); + if (ret != sizeof(*p)) + return ksft_test_result_fail("PMLEN=%d ABI enabled write\n", pmlen); + + ret = read(dev_zero, p, sizeof(*p)); + if (ret != sizeof(*p)) + return ksft_test_result_fail("PMLEN=%d ABI enabled read\n", pmlen); + + if (i) + return ksft_test_result_fail("PMLEN=%d ABI enabled value\n", pmlen); + + i = ~pmlen; + } else { + /* The tagged address ABI cannot be enabled when PMLEN == 0. */ + ret = set_tagged_addr_ctrl(pmlen, true); + if (ret != -EINVAL) + return ksft_test_result_error("PMLEN=%d ABI setup (%d)\n", + pmlen, ret); + } + + p = (int *)((uintptr_t)&i | 1UL << (__riscv_xlen - pmlen - 1)); + + ret = write(pipefd[1], p, sizeof(*p)); + if (ret >= 0 || errno != EFAULT) + return ksft_test_result_fail("PMLEN=%d invalid tag write (%d)\n", pmlen, errno); + + ret = read(dev_zero, p, sizeof(*p)); + if (ret >= 0 || errno != EFAULT) + return ksft_test_result_fail("PMLEN=%d invalid tag read\n", pmlen); + + if (i != ~pmlen) + return ksft_test_result_fail("PMLEN=%d invalid tag value\n", pmlen); + + ksft_test_result_pass("PMLEN=%d tagged address ABI\n", pmlen); +} + +static void test_tagged_addr_abi(void) +{ + ksft_print_msg("Testing tagged address ABI\n"); + + test_tagged_addr_abi_pmlen(0); + test_tagged_addr_abi_pmlen(min_pmlen); + test_tagged_addr_abi_pmlen(max_pmlen); +} + +static struct test_info { + unsigned int nr_tests; + void (*test_fn)(void); +} tests[] = { + { .nr_tests = 17 * 3, test_pmlen }, + { .nr_tests = 3, test_dereference }, + { .nr_tests = 2, test_fork_exec }, + { .nr_tests = 2, test_tagged_addr_abi_sysctl }, + { .nr_tests = 3, test_tagged_addr_abi }, +}; + +int main(int argc, char **argv) +{ + unsigned int plan = 0; + int ret; + + /* Check if this is the child process after execve(). */ + if (!argv[0][0]) + return execve_child(); + + dev_zero = open("/dev/zero", O_RDWR); + if (dev_zero < 0) + return 1; + + /* Write to a pipe so the kernel must dereference the buffer pointer. */ + ret = pipe(pipefd); + if (ret) + return 1; + + ksft_print_header(); + + for (int i = 0; i < ARRAY_SIZE(tests); i++) + plan += tests[i].nr_tests; + + ksft_set_plan(plan); + + for (int i = 0; i < ARRAY_SIZE(tests); i++) + tests[i].test_fn(); + + ksft_finished(); +} From 411944dffa891399fd36f099b795e4c0aed6f3cc Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Wed, 16 Oct 2024 13:27:51 -0700 Subject: [PATCH 06/10] KVM: riscv: selftests: Add Smnpm and Ssnpm to get-reg-list test mainline inclusion from Linux 6.13-rc1 commit 036a1407b4d49790ca5b35436d02de62212bc790 category: feature bugzilla: https://github.com/RVCK-Project/rvck/issues/335 -------------------------------- Add testing for the pointer masking extensions exposed to KVM guests. Reviewed-by: Anup Patel Signed-off-by: Samuel Holland Signed-off-by: Fangyu Yu --- tools/testing/selftests/kvm/riscv/get-reg-list.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/tools/testing/selftests/kvm/riscv/get-reg-list.c b/tools/testing/selftests/kvm/riscv/get-reg-list.c index 9204f9696606..6510c98a85b0 100644 --- a/tools/testing/selftests/kvm/riscv/get-reg-list.c +++ b/tools/testing/selftests/kvm/riscv/get-reg-list.c @@ -41,9 +41,11 @@ bool filter_reg(__u64 reg) case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_I: case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_M: case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_V: + case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SMNPM: case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SMSTATEEN: case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SSAIA: case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SSCOFPMF: + case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SSNPM: case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SSTC: case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SVINVAL: case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SVNAPOT: @@ -392,8 +394,10 @@ static const char *isa_ext_id_to_str(const char *prefix, __u64 id) KVM_ISA_EXT_ARR(I), KVM_ISA_EXT_ARR(M), KVM_ISA_EXT_ARR(V), + KVM_ISA_EXT_ARR(SMNPM), KVM_ISA_EXT_ARR(SSAIA), KVM_ISA_EXT_ARR(SSCOFPMF), + KVM_ISA_EXT_ARR(SSNPM), KVM_ISA_EXT_ARR(SSTC), KVM_ISA_EXT_ARR(SVINVAL), KVM_ISA_EXT_ARR(SVNAPOT), @@ -863,8 +867,10 @@ KVM_ISA_EXT_SUBLIST_CONFIG(aia, AIA); KVM_ISA_EXT_SUBLIST_CONFIG(fp_f, FP_F); KVM_ISA_EXT_SUBLIST_CONFIG(fp_d, FP_D); KVM_ISA_EXT_SIMPLE_CONFIG(h, H); +KVM_ISA_EXT_SIMPLE_CONFIG(smnpm, SMNPM); KVM_ISA_EXT_SUBLIST_CONFIG(smstateen, SMSTATEEN); KVM_ISA_EXT_SIMPLE_CONFIG(sscofpmf, SSCOFPMF); +KVM_ISA_EXT_SIMPLE_CONFIG(ssnpm, SSNPM); KVM_ISA_EXT_SIMPLE_CONFIG(sstc, SSTC); KVM_ISA_EXT_SIMPLE_CONFIG(svinval, SVINVAL); KVM_ISA_EXT_SIMPLE_CONFIG(svnapot, SVNAPOT); @@ -894,8 +900,10 @@ struct vcpu_reg_list *vcpu_configs[] = { &config_fp_f, &config_fp_d, &config_h, + &config_smnpm, &config_smstateen, &config_sscofpmf, + &config_ssnpm, &config_sstc, &config_svinval, &config_svnapot, From f336e8fbc3612d6505778694af7cbf97f3ab03ee Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Wed, 3 Jan 2024 13:00:20 -0300 Subject: [PATCH 07/10] riscv: Replace direct thread flag check with is_compat_task() mainline inclusion from Linux 6.9-rc1 commit 9dc30419248f78dfebea7a554ec212dd1d82f8d7 category: feature bugzilla: https://github.com/RVCK-Project/rvck/issues/335 -------------------------------- There is some code that detects compat mode into a task by checking the flag directly, and other code that check using the helper is_compat_task(). Since the helper already exists, use it instead of checking the flags directly. Signed-off-by: Leonardo Bras Signed-off-by: Fangyu Yu --- arch/riscv/include/asm/elf.h | 2 +- arch/riscv/include/asm/pgtable.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h index 06c236bfab53..59a08367fddd 100644 --- a/arch/riscv/include/asm/elf.h +++ b/arch/riscv/include/asm/elf.h @@ -54,7 +54,7 @@ extern bool compat_elf_check_arch(Elf32_Ehdr *hdr); #ifdef CONFIG_64BIT #ifdef CONFIG_COMPAT -#define STACK_RND_MASK (test_thread_flag(TIF_32BIT) ? \ +#define STACK_RND_MASK (is_compat_task() ? \ 0x7ff >> (PAGE_SHIFT - 12) : \ 0x3ffff >> (PAGE_SHIFT - 12)) #else diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index d3b906a4bdb6..39f458658d61 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -1016,7 +1016,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte) #ifdef CONFIG_COMPAT #define TASK_SIZE_32 (_AC(0x80000000, UL)) -#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \ +#define TASK_SIZE (is_compat_task() ? \ TASK_SIZE_32 : TASK_SIZE_64) #else #define TASK_SIZE TASK_SIZE_64 From acd890bb3f38c8476412819ac08b8ad26c2581dd Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Wed, 3 Jan 2024 13:00:21 -0300 Subject: [PATCH 08/10] riscv: add compile-time test into is_compat_task() mainline inclusion from Linux 6.9-rc1 commit 4c0b5a451675e9a95be98a16ddb889bb0486d2ad category: feature bugzilla: https://github.com/RVCK-Project/rvck/issues/335 -------------------------------- Currently several places will test for CONFIG_COMPAT before testing is_compat_task(), probably in order to avoid a run-time test into the task structure. Since is_compat_task() is an inlined function, it would be helpful to add a compile-time test of CONFIG_COMPAT, making sure it always returns zero when the option is not enabled during the kernel build. With this, the compiler is able to understand in build-time that is_compat_task() will always return 0, and optimize-out some of the extra code introduced by the option. This will also allow removing a lot #ifdefs that were introduced, and make the code more clean. Signed-off-by: Leonardo Bras Reviewed-by: Guo Ren Reviewed-by: Andy Chiu Signed-off-by: Fangyu Yu --- arch/riscv/include/asm/compat.h | 3 +++ arch/riscv/include/asm/elf.h | 4 ---- arch/riscv/include/asm/pgtable.h | 6 ------ 3 files changed, 3 insertions(+), 10 deletions(-) diff --git a/arch/riscv/include/asm/compat.h b/arch/riscv/include/asm/compat.h index 2290b8b9b16f..75a487578ef2 100644 --- a/arch/riscv/include/asm/compat.h +++ b/arch/riscv/include/asm/compat.h @@ -13,6 +13,9 @@ static inline int is_compat_task(void) { + if (!IS_ENABLED(CONFIG_COMPAT)) + return 0; + return test_thread_flag(TIF_32BIT); } diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h index 59a08367fddd..2e88257cafae 100644 --- a/arch/riscv/include/asm/elf.h +++ b/arch/riscv/include/asm/elf.h @@ -53,13 +53,9 @@ extern bool compat_elf_check_arch(Elf32_Ehdr *hdr); #define ELF_ET_DYN_BASE ((DEFAULT_MAP_WINDOW / 3) * 2) #ifdef CONFIG_64BIT -#ifdef CONFIG_COMPAT #define STACK_RND_MASK (is_compat_task() ? \ 0x7ff >> (PAGE_SHIFT - 12) : \ 0x3ffff >> (PAGE_SHIFT - 12)) -#else -#define STACK_RND_MASK (0x3ffff >> (PAGE_SHIFT - 12)) -#endif #endif /* diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 39f458658d61..b7d322b79803 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -141,16 +141,10 @@ #define VA_USER_SV48 (UL(1) << (VA_BITS_SV48 - 1)) #define VA_USER_SV57 (UL(1) << (VA_BITS_SV57 - 1)) -#ifdef CONFIG_COMPAT #define MMAP_VA_BITS_64 ((VA_BITS >= VA_BITS_SV48) ? VA_BITS_SV48 : VA_BITS) #define MMAP_MIN_VA_BITS_64 (VA_BITS_SV39) #define MMAP_VA_BITS (is_compat_task() ? VA_BITS_SV32 : MMAP_VA_BITS_64) #define MMAP_MIN_VA_BITS (is_compat_task() ? VA_BITS_SV32 : MMAP_MIN_VA_BITS_64) -#else -#define MMAP_VA_BITS ((VA_BITS >= VA_BITS_SV48) ? VA_BITS_SV48 : VA_BITS) -#define MMAP_MIN_VA_BITS (VA_BITS_SV39) -#endif /* CONFIG_COMPAT */ - #else #include #endif /* CONFIG_64BIT */ From b632ce0475d4c8d06ebb2f8936317134cf2c4f36 Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Wed, 3 Jan 2024 13:00:22 -0300 Subject: [PATCH 09/10] riscv: Introduce is_compat_thread() into compat.h mainline inclusion from Linux 6.9-rc1 commit 5917ea17ad07f35bb5be4fd5fdcd408f090e347b category: feature bugzilla: https://github.com/RVCK-Project/rvck/issues/335 -------------------------------- task_user_regset_view() makes use of a function very similar to is_compat_task(), but pointing to a any thread. In arm64 asm/compat.h there is a function very similar to that: is_compat_thread(struct thread_info *thread) Copy this function to riscv asm/compat.h and make use of it into task_user_regset_view(). Also, introduce a compile-time test for CONFIG_COMPAT and simplify the function code by removing the #ifdef. Signed-off-by: Leonardo Bras Reviewed-by: Guo Ren Reviewed-by: Andy Chiu Signed-off-by: Fangyu Yu --- arch/riscv/include/asm/compat.h | 8 ++++++++ arch/riscv/kernel/ptrace.c | 6 +++--- 2 files changed, 11 insertions(+), 3 deletions(-) diff --git a/arch/riscv/include/asm/compat.h b/arch/riscv/include/asm/compat.h index 75a487578ef2..6517e91196ad 100644 --- a/arch/riscv/include/asm/compat.h +++ b/arch/riscv/include/asm/compat.h @@ -19,6 +19,14 @@ static inline int is_compat_task(void) return test_thread_flag(TIF_32BIT); } +static inline int is_compat_thread(struct thread_info *thread) +{ + if (!IS_ENABLED(CONFIG_COMPAT)) + return 0; + + return test_ti_thread_flag(thread, TIF_32BIT); +} + struct compat_user_regs_struct { compat_ulong_t pc; compat_ulong_t ra; diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c index 998147b7be5c..889d85bf3c6b 100644 --- a/arch/riscv/kernel/ptrace.c +++ b/arch/riscv/kernel/ptrace.c @@ -514,14 +514,14 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, return ret; } +#else +static const struct user_regset_view compat_riscv_user_native_view = {}; #endif /* CONFIG_COMPAT */ const struct user_regset_view *task_user_regset_view(struct task_struct *task) { -#ifdef CONFIG_COMPAT - if (test_tsk_thread_flag(task, TIF_32BIT)) + if (is_compat_thread(&task->thread_info)) return &compat_riscv_user_native_view; else -#endif return &riscv_user_native_view; } From 7c1cda7018cf59c862f2cf1458a758802d3deefc Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Wed, 3 Jan 2024 13:00:23 -0300 Subject: [PATCH 10/10] riscv: Introduce set_compat_task() in asm/compat.h mainline inclusion from Linux 6.9-rc1 commit 2a8986fc5e1cb686dd3aae3022459aea23b9823a category: feature bugzilla: https://github.com/RVCK-Project/rvck/issues/335 -------------------------------- In order to have all task compat bit access directly in compat.h, introduce set_compat_task() to set/reset those when needed. Also, since it's only used on an if/else scenario, simplify the macro using it. Signed-off-by: Leonardo Bras Reviewed-by: Guo Ren Signed-off-by: Fangyu Yu --- arch/riscv/include/asm/compat.h | 8 ++++++++ arch/riscv/include/asm/elf.h | 5 +---- 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/riscv/include/asm/compat.h b/arch/riscv/include/asm/compat.h index 6517e91196ad..28e115eed218 100644 --- a/arch/riscv/include/asm/compat.h +++ b/arch/riscv/include/asm/compat.h @@ -27,6 +27,14 @@ static inline int is_compat_thread(struct thread_info *thread) return test_ti_thread_flag(thread, TIF_32BIT); } +static inline void set_compat_task(bool is_compat) +{ + if (is_compat) + set_thread_flag(TIF_32BIT); + else + clear_thread_flag(TIF_32BIT); +} + struct compat_user_regs_struct { compat_ulong_t pc; compat_ulong_t ra; diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h index 2e88257cafae..c7aea7886d22 100644 --- a/arch/riscv/include/asm/elf.h +++ b/arch/riscv/include/asm/elf.h @@ -135,10 +135,7 @@ do { \ #ifdef CONFIG_COMPAT #define SET_PERSONALITY(ex) \ -do { if ((ex).e_ident[EI_CLASS] == ELFCLASS32) \ - set_thread_flag(TIF_32BIT); \ - else \ - clear_thread_flag(TIF_32BIT); \ +do { set_compat_task((ex).e_ident[EI_CLASS] == ELFCLASS32); \ if (personality(current->personality) != PER_LINUX32) \ set_personality(PER_LINUX | \ (current->personality & (~PER_MASK))); \