From 75df38aaf1f102af32919fad2e055153bee52e1f Mon Sep 17 00:00:00 2001 From: Hongbo Li Date: Wed, 4 Sep 2024 09:16:42 +0800 Subject: [PATCH 1/7] parisc: pdc_stable: Constify struct kobj_type This 'struct kobj_type' is not modified. It is only used in kobject_init_and_add() which takes a 'const struct kobj_type *ktype' parameter. Constifying this structure and moving it to a read-only section, and can increase over all security. Signed-off-by: Hongbo Li Signed-off-by: Helge Deller --- drivers/parisc/pdc_stable.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/parisc/pdc_stable.c b/drivers/parisc/pdc_stable.c index 633266447e2f..16f4496bca95 100644 --- a/drivers/parisc/pdc_stable.c +++ b/drivers/parisc/pdc_stable.c @@ -483,7 +483,7 @@ static struct attribute *paths_subsys_attrs[] = { ATTRIBUTE_GROUPS(paths_subsys); /* Specific kobject type for our PDC paths */ -static struct kobj_type ktype_pdcspath = { +static const struct kobj_type ktype_pdcspath = { .sysfs_ops = &pdcspath_attr_ops, .default_groups = paths_subsys_groups, }; From b5ff52be891347f8847872c49d7a5c2fa29400a7 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Sat, 31 Aug 2024 14:26:53 +0200 Subject: [PATCH 2/7] parisc: Convert to generic clockevents Convert parisc timer code to generic clockevents framework. Signed-off-by: Helge Deller --- arch/parisc/Kconfig | 2 +- arch/parisc/include/asm/processor.h | 2 +- arch/parisc/kernel/smp.c | 2 +- arch/parisc/kernel/time.c | 251 +++++++++++----------------- 4 files changed, 103 insertions(+), 154 deletions(-) diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index b0a2ac3ba916..db3edd54d6f2 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -72,7 +72,7 @@ config PARISC select GENERIC_SCHED_CLOCK select GENERIC_IRQ_MIGRATION if SMP select HAVE_UNSTABLE_SCHED_CLOCK if SMP - select LEGACY_TIMER_TICK + select GENERIC_CLOCKEVENTS select CPU_NO_EFFICIENT_FFS select THREAD_INFO_IN_TASK select NEED_DMA_MAP_STATE diff --git a/arch/parisc/include/asm/processor.h b/arch/parisc/include/asm/processor.h index 982aca20f56f..77fac02188e1 100644 --- a/arch/parisc/include/asm/processor.h +++ b/arch/parisc/include/asm/processor.h @@ -298,7 +298,7 @@ extern unsigned int toc_handler_csum; extern void do_cpu_irq_mask(struct pt_regs *); extern irqreturn_t timer_interrupt(int, void *); extern irqreturn_t ipi_interrupt(int, void *); -extern void start_cpu_itimer(void); +extern void parisc_clockevent_init(void); extern void handle_interruption(int, struct pt_regs *); /* called from assembly code: */ diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c index 800eb64e91ad..b2d12ab728b1 100644 --- a/arch/parisc/kernel/smp.c +++ b/arch/parisc/kernel/smp.c @@ -297,7 +297,7 @@ smp_cpu_init(int cpunum) enter_lazy_tlb(&init_mm, current); init_IRQ(); /* make sure no IRQs are enabled or pending */ - start_cpu_itimer(); + parisc_clockevent_init(); } diff --git a/arch/parisc/kernel/time.c b/arch/parisc/kernel/time.c index 9714fbd7c42d..c17e2249115f 100644 --- a/arch/parisc/kernel/time.c +++ b/arch/parisc/kernel/time.c @@ -1,126 +1,105 @@ // SPDX-License-Identifier: GPL-2.0 /* - * linux/arch/parisc/kernel/time.c + * Common time service routines for parisc machines. + * based on arch/loongarch/kernel/time.c * - * Copyright (C) 1991, 1992, 1995 Linus Torvalds - * Modifications for ARM (C) 1994, 1995, 1996,1997 Russell King - * Copyright (C) 1999 SuSE GmbH, (Philipp Rumpf, prumpf@tux.org) - * - * 1994-07-02 Alan Modra - * fixed set_rtc_mmss, fixed time.year for >= 2000, new mktime - * 1998-12-20 Updated NTP code according to technical memorandum Jan '96 - * "A Kernel Model for Precision Timekeeping" by Dave Mills + * Copyright (C) 2024 Helge Deller */ -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include +#include +#include +#include #include -#include -#include -#include +#include +#include +#include +#include +#include #include -#include +#include -#include -#include -#include -#include -#include -#include -#include +static u64 cr16_clock_freq; +static unsigned long clocktick; -#include +int time_keeper_id; /* CPU used for timekeeping */ -int time_keeper_id __read_mostly; /* CPU used for timekeeping. */ +static DEFINE_PER_CPU(struct clock_event_device, parisc_clockevent_device); -static unsigned long clocktick __ro_after_init; /* timer cycles per tick */ - -/* - * We keep time on PA-RISC Linux by using the Interval Timer which is - * a pair of registers; one is read-only and one is write-only; both - * accessed through CR16. The read-only register is 32 or 64 bits wide, - * and increments by 1 every CPU clock tick. The architecture only - * guarantees us a rate between 0.5 and 2, but all implementations use a - * rate of 1. The write-only register is 32-bits wide. When the lowest - * 32 bits of the read-only register compare equal to the write-only - * register, it raises a maskable external interrupt. Each processor has - * an Interval Timer of its own and they are not synchronised. - * - * We want to generate an interrupt every 1/HZ seconds. So we program - * CR16 to interrupt every @clocktick cycles. The it_value in cpu_data - * is programmed with the intended time of the next tick. We can be - * held off for an arbitrarily long period of time by interrupts being - * disabled, so we may miss one or more ticks. - */ -irqreturn_t __irq_entry timer_interrupt(int irq, void *dev_id) +static void parisc_event_handler(struct clock_event_device *dev) { - unsigned long now; - unsigned long next_tick; - unsigned long ticks_elapsed = 0; - unsigned int cpu = smp_processor_id(); - struct cpuinfo_parisc *cpuinfo = &per_cpu(cpu_data, cpu); +} - /* gcc can optimize for "read-only" case with a local clocktick */ - unsigned long cpt = clocktick; +static int parisc_timer_next_event(unsigned long delta, struct clock_event_device *evt) +{ + unsigned long new_cr16; - /* Initialize next_tick to the old expected tick time. */ - next_tick = cpuinfo->it_value; + new_cr16 = mfctl(16) + delta; + mtctl(new_cr16, 16); - /* Calculate how many ticks have elapsed. */ - now = mfctl(16); - do { - ++ticks_elapsed; - next_tick += cpt; - } while (next_tick - now > cpt); + return 0; +} - /* Store (in CR16 cycles) up to when we are accounting right now. */ - cpuinfo->it_value = next_tick; +irqreturn_t timer_interrupt(int irq, void *data) +{ + struct clock_event_device *cd; + int cpu = smp_processor_id(); - /* Go do system house keeping. */ - if (IS_ENABLED(CONFIG_SMP) && (cpu != time_keeper_id)) - ticks_elapsed = 0; - legacy_timer_tick(ticks_elapsed); + cd = &per_cpu(parisc_clockevent_device, cpu); - /* Skip clockticks on purpose if we know we would miss those. - * The new CR16 must be "later" than current CR16 otherwise - * itimer would not fire until CR16 wrapped - e.g 4 seconds - * later on a 1Ghz processor. We'll account for the missed - * ticks on the next timer interrupt. - * We want IT to fire modulo clocktick even if we miss/skip some. - * But those interrupts don't in fact get delivered that regularly. - * - * "next_tick - now" will always give the difference regardless - * if one or the other wrapped. If "now" is "bigger" we'll end up - * with a very large unsigned number. - */ - now = mfctl(16); - while (next_tick - now > cpt) - next_tick += cpt; + if (clockevent_state_periodic(cd)) + parisc_timer_next_event(clocktick, cd); - /* Program the IT when to deliver the next interrupt. - * Only bottom 32-bits of next_tick are writable in CR16! - * Timer interrupt will be delivered at least a few hundred cycles - * after the IT fires, so if we are too close (<= 8000 cycles) to the - * next cycle, simply skip it. - */ - if (next_tick - now <= 8000) - next_tick += cpt; - mtctl(next_tick, 16); + if (clockevent_state_periodic(cd) || clockevent_state_oneshot(cd)) + cd->event_handler(cd); return IRQ_HANDLED; } +static int parisc_set_state_oneshot(struct clock_event_device *evt) +{ + parisc_timer_next_event(clocktick, evt); -unsigned long profile_pc(struct pt_regs *regs) + return 0; +} + +static int parisc_set_state_periodic(struct clock_event_device *evt) +{ + parisc_timer_next_event(clocktick, evt); + + return 0; +} + +static int parisc_set_state_shutdown(struct clock_event_device *evt) +{ + return 0; +} + +void parisc_clockevent_init(void) +{ + unsigned int cpu = smp_processor_id(); + unsigned long min_delta = 0x600; /* XXX */ + unsigned long max_delta = (1UL << (BITS_PER_LONG - 1)); + struct clock_event_device *cd; + + cd = &per_cpu(parisc_clockevent_device, cpu); + + cd->name = "cr16_clockevent"; + cd->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_PERCPU; + + cd->irq = TIMER_IRQ; + cd->rating = 320; + cd->cpumask = cpumask_of(cpu); + cd->set_state_oneshot = parisc_set_state_oneshot; + cd->set_state_oneshot_stopped = parisc_set_state_shutdown; + cd->set_state_periodic = parisc_set_state_periodic; + cd->set_state_shutdown = parisc_set_state_shutdown; + cd->set_next_event = parisc_timer_next_event; + cd->event_handler = parisc_event_handler; + + clockevents_config_and_register(cd, cr16_clock_freq, min_delta, max_delta); +} + +unsigned long notrace profile_pc(struct pt_regs *regs) { unsigned long pc = instruction_pointer(regs); @@ -136,32 +115,6 @@ unsigned long profile_pc(struct pt_regs *regs) } EXPORT_SYMBOL(profile_pc); - -/* clock source code */ - -static u64 notrace read_cr16(struct clocksource *cs) -{ - return get_cycles(); -} - -static struct clocksource clocksource_cr16 = { - .name = "cr16", - .rating = 300, - .read = read_cr16, - .mask = CLOCKSOURCE_MASK(BITS_PER_LONG), - .flags = CLOCK_SOURCE_IS_CONTINUOUS, -}; - -void start_cpu_itimer(void) -{ - unsigned int cpu = smp_processor_id(); - unsigned long next_tick = mfctl(16) + clocktick; - - mtctl(next_tick, 16); /* kick off Interval Timer (CR16) */ - - per_cpu(cpu_data, cpu).it_value = next_tick; -} - #if IS_ENABLED(CONFIG_RTC_DRV_GENERIC) static int rtc_generic_get_time(struct device *dev, struct rtc_time *tm) { @@ -224,12 +177,27 @@ void read_persistent_clock64(struct timespec64 *ts) } } - static u64 notrace read_cr16_sched_clock(void) { return get_cycles(); } +static u64 notrace read_cr16(struct clocksource *cs) +{ + return get_cycles(); +} + +static struct clocksource clocksource_cr16 = { + .name = "cr16", + .rating = 300, + .read = read_cr16, + .mask = CLOCKSOURCE_MASK(BITS_PER_LONG), + .flags = CLOCK_SOURCE_IS_CONTINUOUS | + CLOCK_SOURCE_VALID_FOR_HRES | + CLOCK_SOURCE_MUST_VERIFY | + CLOCK_SOURCE_VERIFY_PERCPU, +}; + /* * timer interrupt and sched_clock() initialization @@ -237,33 +205,14 @@ static u64 notrace read_cr16_sched_clock(void) void __init time_init(void) { - unsigned long cr16_hz; - - clocktick = (100 * PAGE0->mem_10msec) / HZ; - start_cpu_itimer(); /* get CPU 0 started */ - - cr16_hz = 100 * PAGE0->mem_10msec; /* Hz */ + cr16_clock_freq = 100 * PAGE0->mem_10msec; /* Hz */ + clocktick = cr16_clock_freq / HZ; /* register as sched_clock source */ - sched_clock_register(read_cr16_sched_clock, BITS_PER_LONG, cr16_hz); -} + sched_clock_register(read_cr16_sched_clock, BITS_PER_LONG, cr16_clock_freq); -static int __init init_cr16_clocksource(void) -{ - /* - * The cr16 interval timers are not synchronized across CPUs. - */ - if (num_online_cpus() > 1 && !running_on_qemu) { - clocksource_cr16.name = "cr16_unstable"; - clocksource_cr16.flags = CLOCK_SOURCE_UNSTABLE; - clocksource_cr16.rating = 0; - } + parisc_clockevent_init(); /* register at clocksource framework */ - clocksource_register_hz(&clocksource_cr16, - 100 * PAGE0->mem_10msec); - - return 0; + clocksource_register_hz(&clocksource_cr16, cr16_clock_freq); } - -device_initcall(init_cr16_clocksource); From f31b256994acec6929306dfa86ac29716e7503d6 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Sat, 7 Sep 2024 18:28:11 +0200 Subject: [PATCH 3/7] parisc: Fix stack start for ADDR_NO_RANDOMIZE personality Fix the stack start address calculation for the parisc architecture in setup_arg_pages() when address randomization is disabled. When the ADDR_NO_RANDOMIZE process personality is disabled there is no need to add additional space for the stack. Note that this patch touches code inside an #ifdef CONFIG_STACK_GROWSUP hunk, which is why only the parisc architecture is affected since it's the only Linux architecture where the stack grows upwards. Without this patch you will find the stack in the middle of some mapped libaries and suddenly limited to 6MB instead of 8MB: root@parisc:~# setarch -R /bin/bash -c "cat /proc/self/maps" 00010000-00019000 r-xp 00000000 08:05 1182034 /usr/bin/cat 00019000-0001a000 rwxp 00009000 08:05 1182034 /usr/bin/cat 0001a000-0003b000 rwxp 00000000 00:00 0 [heap] f90c4000-f9283000 r-xp 00000000 08:05 1573004 /usr/lib/hppa-linux-gnu/libc.so.6 f9283000-f9285000 r--p 001bf000 08:05 1573004 /usr/lib/hppa-linux-gnu/libc.so.6 f9285000-f928a000 rwxp 001c1000 08:05 1573004 /usr/lib/hppa-linux-gnu/libc.so.6 f928a000-f9294000 rwxp 00000000 00:00 0 f9301000-f9323000 rwxp 00000000 00:00 0 [stack] f98b4000-f98e4000 r-xp 00000000 08:05 1572869 /usr/lib/hppa-linux-gnu/ld.so.1 f98e4000-f98e5000 r--p 00030000 08:05 1572869 /usr/lib/hppa-linux-gnu/ld.so.1 f98e5000-f98e9000 rwxp 00031000 08:05 1572869 /usr/lib/hppa-linux-gnu/ld.so.1 f9ad8000-f9b00000 rw-p 00000000 00:00 0 f9b00000-f9b01000 r-xp 00000000 00:00 0 [vdso] With the patch the stack gets correctly mapped at the end of the process memory map: root@panama:~# setarch -R /bin/bash -c "cat /proc/self/maps" 00010000-00019000 r-xp 00000000 08:13 16385582 /usr/bin/cat 00019000-0001a000 rwxp 00009000 08:13 16385582 /usr/bin/cat 0001a000-0003b000 rwxp 00000000 00:00 0 [heap] fef29000-ff0eb000 r-xp 00000000 08:13 16122400 /usr/lib/hppa-linux-gnu/libc.so.6 ff0eb000-ff0ed000 r--p 001c2000 08:13 16122400 /usr/lib/hppa-linux-gnu/libc.so.6 ff0ed000-ff0f2000 rwxp 001c4000 08:13 16122400 /usr/lib/hppa-linux-gnu/libc.so.6 ff0f2000-ff0fc000 rwxp 00000000 00:00 0 ff4b4000-ff4e4000 r-xp 00000000 08:13 16121913 /usr/lib/hppa-linux-gnu/ld.so.1 ff4e4000-ff4e6000 r--p 00030000 08:13 16121913 /usr/lib/hppa-linux-gnu/ld.so.1 ff4e6000-ff4ea000 rwxp 00032000 08:13 16121913 /usr/lib/hppa-linux-gnu/ld.so.1 ff6d7000-ff6ff000 rw-p 00000000 00:00 0 ff6ff000-ff700000 r-xp 00000000 00:00 0 [vdso] ff700000-ff722000 rwxp 00000000 00:00 0 [stack] Reported-by: Camm Maguire Signed-off-by: Helge Deller Fixes: d045c77c1a69 ("parisc,metag: Fix crashes due to stack randomization on stack-grows-upwards architectures") Fixes: 17d9822d4b4c ("parisc: Consider stack randomization for mmap base only when necessary") Cc: stable@vger.kernel.org # v5.2+ --- fs/exec.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/exec.c b/fs/exec.c index 50e76cc633c4..00c968a739c3 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -813,7 +813,8 @@ int setup_arg_pages(struct linux_binprm *bprm, stack_base = calc_max_stack_size(stack_base); /* Add space for stack randomization. */ - stack_base += (STACK_RND_MASK << PAGE_SHIFT); + if (current->flags & PF_RANDOMIZE) + stack_base += (STACK_RND_MASK << PAGE_SHIFT); /* Make sure we didn't let the argument array grow too large. */ if (vma->vm_end - vma->vm_start > stack_base) From d24449864da5838936669618356b0e30ca2999c3 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Sun, 8 Sep 2024 00:40:38 +0200 Subject: [PATCH 4/7] parisc: Fix 64-bit userspace syscall path Currently the glibc isn't yet ported to 64-bit for hppa, so there is no usable userspace available yet. But it's possible to manually build a static 64-bit binary and run that for testing. One such 64-bit test program is available at http://ftp.parisc-linux.org/src/64bit.tar.gz and it shows various issues with the existing 64-bit syscall path in the kernel. This patch fixes those issues. Signed-off-by: Helge Deller Cc: stable@vger.kernel.org # v4.19+ --- arch/parisc/kernel/syscall.S | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S index 1f51aa9c8230..0fa81bf1466b 100644 --- a/arch/parisc/kernel/syscall.S +++ b/arch/parisc/kernel/syscall.S @@ -243,10 +243,10 @@ linux_gateway_entry: #ifdef CONFIG_64BIT ldil L%sys_call_table, %r1 - or,= %r2,%r2,%r2 - addil L%(sys_call_table64-sys_call_table), %r1 + or,ev %r2,%r2,%r2 + ldil L%sys_call_table64, %r1 ldo R%sys_call_table(%r1), %r19 - or,= %r2,%r2,%r2 + or,ev %r2,%r2,%r2 ldo R%sys_call_table64(%r1), %r19 #else load32 sys_call_table, %r19 @@ -379,10 +379,10 @@ tracesys_next: extrd,u %r19,63,1,%r2 /* W hidden in bottom bit */ ldil L%sys_call_table, %r1 - or,= %r2,%r2,%r2 - addil L%(sys_call_table64-sys_call_table), %r1 + or,ev %r2,%r2,%r2 + ldil L%sys_call_table64, %r1 ldo R%sys_call_table(%r1), %r19 - or,= %r2,%r2,%r2 + or,ev %r2,%r2,%r2 ldo R%sys_call_table64(%r1), %r19 #else load32 sys_call_table, %r19 @@ -1327,6 +1327,8 @@ ENTRY(sys_call_table) END(sys_call_table) #ifdef CONFIG_64BIT +#undef __SYSCALL_WITH_COMPAT +#define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, native) .align 8 ENTRY(sys_call_table64) #include /* 64-bit syscalls */ From 9542130937e9dc707dd7c6b7af73326437da2d50 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Tue, 10 Sep 2024 18:32:24 +0200 Subject: [PATCH 5/7] parisc: Fix itlb miss handler for 64-bit programs For an itlb miss when executing code above 4 Gb on ILP64 adjust the iasq/iaoq in the same way isr/ior was adjusted. This fixes signal delivery for the 64-bit static test program from http://ftp.parisc-linux.org/src/64bit.tar.gz. Note that signals are handled by the signal trampoline code in the 64-bit VDSO which is mapped into high userspace memory region above 4GB for 64-bit processes. Signed-off-by: Helge Deller Cc: stable@vger.kernel.org # v4.19+ --- arch/parisc/kernel/entry.S | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S index ab23e61a6f01..ea57bcc21dc5 100644 --- a/arch/parisc/kernel/entry.S +++ b/arch/parisc/kernel/entry.S @@ -1051,8 +1051,7 @@ ENTRY_CFI(intr_save) /* for os_hpmc */ STREG %r16, PT_ISR(%r29) STREG %r17, PT_IOR(%r29) -#if 0 && defined(CONFIG_64BIT) - /* Revisit when we have 64-bit code above 4Gb */ +#if defined(CONFIG_64BIT) b,n intr_save2 skip_save_ior: @@ -1060,8 +1059,7 @@ skip_save_ior: * need to adjust iasq/iaoq here in the same way we adjusted isr/ior * above. */ - extrd,u,* %r8,PSW_W_BIT,1,%r1 - cmpib,COND(=),n 1,%r1,intr_save2 + bb,COND(>=),n %r8,PSW_W_BIT,intr_save2 LDREG PT_IASQ0(%r29), %r16 LDREG PT_IAOQ0(%r29), %r17 /* adjust iasq/iaoq */ From 75f653f0c6318ae0acfd6277efba3f9bd7cf837c Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Tue, 10 Sep 2024 18:42:05 +0200 Subject: [PATCH 6/7] parisc: Use PRIV_USER instead of hardcoded value Signed-off-by: Helge Deller --- arch/parisc/kernel/traps.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/parisc/kernel/traps.c b/arch/parisc/kernel/traps.c index 1107ca819ac8..294b0e026c9a 100644 --- a/arch/parisc/kernel/traps.c +++ b/arch/parisc/kernel/traps.c @@ -504,7 +504,7 @@ void notrace handle_interruption(int code, struct pt_regs *regs) if (((unsigned long)regs->iaoq[0] & 3) && ((unsigned long)regs->iasq[0] != (unsigned long)regs->sr[7])) { /* Kill the user process later */ - regs->iaoq[0] = 0 | 3; + regs->iaoq[0] = 0 | PRIV_USER; regs->iaoq[1] = regs->iaoq[0] + 4; regs->iasq[0] = regs->iasq[1] = regs->sr[7]; regs->gr[0] &= ~PSW_B; From 5d698966fa7b452035c44c937d704910bf3440dd Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Sun, 8 Sep 2024 20:51:17 +0200 Subject: [PATCH 7/7] parisc: Allow mmap(MAP_STACK) memory to automatically expand upwards When userspace allocates memory with mmap() in order to be used for stack, allow this memory region to automatically expand upwards up until the current maximum process stack size. The fault handler checks if the VM_GROWSUP bit is set in the vm_flags field of a memory area before it allows it to expand. This patch modifies the parisc specific code only. A RFC for a generic patch to modify mmap() for all architectures was sent to the mailing list but did not get enough Acks. Reported-by: Camm Maguire Signed-off-by: Helge Deller Cc: stable@vger.kernel.org # v5.10+ --- arch/parisc/include/asm/mman.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/arch/parisc/include/asm/mman.h b/arch/parisc/include/asm/mman.h index 47c5a1991d10..89b6beeda0b8 100644 --- a/arch/parisc/include/asm/mman.h +++ b/arch/parisc/include/asm/mman.h @@ -11,4 +11,18 @@ static inline bool arch_memory_deny_write_exec_supported(void) } #define arch_memory_deny_write_exec_supported arch_memory_deny_write_exec_supported +static inline unsigned long arch_calc_vm_flag_bits(unsigned long flags) +{ + /* + * The stack on parisc grows upwards, so if userspace requests memory + * for a stack, mark it with VM_GROWSUP so that the stack expansion in + * the fault handler will work. + */ + if (flags & MAP_STACK) + return VM_GROWSUP; + + return 0; +} +#define arch_calc_vm_flag_bits(flags) arch_calc_vm_flag_bits(flags) + #endif /* __ASM_MMAN_H__ */