Commit 9d5daef3 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux 

Pull ARM updates from Russell King:

 - add dev_is_amba() function to allow conversions during the next cycle

 - improve PREEMPT_RT performance with VFP

 - KASAN fixes for vmap stack

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux:
  ARM: 9431/1: mm: Pair atomic_set_release() with _read_acquire()
  ARM: 9430/1: entry: Do a dummy read from VMAP shadow
  ARM: 9429/1: ioremap: Sync PGDs for VMALLOC shadow
  ARM: 9426/1: vfp: Move sending signals outside of vfp_state_hold()ed section.
  ARM: 9425/1: vfp: Use vfp_state_hold() in vfp_support_entry().
  ARM: 9424/1: vfp: Use vfp_state_hold() in vfp_sync_hwstate().
  ARM: 9423/1: vfp: Provide vfp_state_hold() for VFP locking.
  ARM: 9415/1: amba: Add dev_is_amba() function and export it for modules
parents fbb3c22f 93ee3852

arch/arm/kernel/entry-armv.S

+8 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include <asm/tls.h>

#include <asm/system_info.h>

#include <asm/uaccess-asm.h>

#include <asm/kasan_def.h>



#include "entry-header.S"

#include <asm/probes.h>
@@ -561,6 +562,13 @@ ENTRY(__switch_to) 
	@ entries covering the vmalloc region.

	@

	ldr	r2, [ip]

#ifdef CONFIG_KASAN_VMALLOC

	@ Also dummy read from the KASAN shadow memory for the new stack if we

	@ are using KASAN

	mov_l	r2, KASAN_SHADOW_OFFSET

	add	r2, r2, ip, lsr #KASAN_SHADOW_SCALE_SHIFT

	ldr	r2, [r2]

#endif

#endif



	@ When CONFIG_THREAD_INFO_IN_TASK=n, the update of SP itself is what

arch/arm/mm/ioremap.c

+30 −5
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ 
 */

#include <linux/module.h>

#include <linux/errno.h>

#include <linux/kasan.h>

#include <linux/mm.h>

#include <linux/vmalloc.h>

#include <linux/io.h>
@@ -115,16 +116,40 @@ int ioremap_page(unsigned long virt, unsigned long phys, 
}

EXPORT_SYMBOL(ioremap_page);



#ifdef CONFIG_KASAN

static unsigned long arm_kasan_mem_to_shadow(unsigned long addr)

{

	return (unsigned long)kasan_mem_to_shadow((void *)addr);

}

#else

static unsigned long arm_kasan_mem_to_shadow(unsigned long addr)

{

	return 0;

}

#endif



static void memcpy_pgd(struct mm_struct *mm, unsigned long start,

		       unsigned long end)

{

	end = ALIGN(end, PGDIR_SIZE);

	memcpy(pgd_offset(mm, start), pgd_offset_k(start),

	       sizeof(pgd_t) * (pgd_index(end) - pgd_index(start)));

}



void __check_vmalloc_seq(struct mm_struct *mm)

{

	int seq;



	do {

		seq = atomic_read(&init_mm.context.vmalloc_seq);

		memcpy(pgd_offset(mm, VMALLOC_START),

		       pgd_offset_k(VMALLOC_START),

		       sizeof(pgd_t) * (pgd_index(VMALLOC_END) -

					pgd_index(VMALLOC_START)));

		seq = atomic_read_acquire(&init_mm.context.vmalloc_seq);

		memcpy_pgd(mm, VMALLOC_START, VMALLOC_END);

		if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) {

			unsigned long start =

				arm_kasan_mem_to_shadow(VMALLOC_START);

			unsigned long end =

				arm_kasan_mem_to_shadow(VMALLOC_END);

			memcpy_pgd(mm, start, end);

		}

		/*

		 * Use a store-release so that other CPUs that observe the

		 * counter's new value are guaranteed to see the results of the

arch/arm/vfp/vfpmodule.c

+53 −21
Original line number Diff line number Diff line
@@ -55,6 +55,34 @@ extern unsigned int VFP_arch_feroceon __alias(VFP_arch); 
 */

union vfp_state *vfp_current_hw_state[NR_CPUS];



/*

 * Claim ownership of the VFP unit.

 *

 * The caller may change VFP registers until vfp_state_release() is called.

 *

 * local_bh_disable() is used to disable preemption and to disable VFP

 * processing in softirq context. On PREEMPT_RT kernels local_bh_disable() is

 * not sufficient because it only serializes soft interrupt related sections

 * via a local lock, but stays preemptible. Disabling preemption is the right

 * choice here as bottom half processing is always in thread context on RT

 * kernels so it implicitly prevents bottom half processing as well.

 */

static void vfp_state_hold(void)

{

	if (!IS_ENABLED(CONFIG_PREEMPT_RT))

		local_bh_disable();

	else

		preempt_disable();

}



static void vfp_state_release(void)

{

	if (!IS_ENABLED(CONFIG_PREEMPT_RT))

		local_bh_enable();

	else

		preempt_enable();

}



/*

 * Is 'thread's most up to date state stored in this CPUs hardware?

 * Must be called from non-preemptible context.
@@ -240,7 +268,7 @@ static void vfp_panic(char *reason, u32 inst) 
/*

 * Process bitmask of exception conditions.

 */

static void vfp_raise_exceptions(u32 exceptions, u32 inst, u32 fpscr, struct pt_regs *regs)

static int vfp_raise_exceptions(u32 exceptions, u32 inst, u32 fpscr)

{

	int si_code = 0;
@@ -248,8 +276,7 @@ static void vfp_raise_exceptions(u32 exceptions, u32 inst, u32 fpscr, struct pt_ 


	if (exceptions == VFP_EXCEPTION_ERROR) {

		vfp_panic("unhandled bounce", inst);

		vfp_raise_sigfpe(FPE_FLTINV, regs);

		return;

		return FPE_FLTINV;

	}



	/*
@@ -277,8 +304,7 @@ static void vfp_raise_exceptions(u32 exceptions, u32 inst, u32 fpscr, struct pt_ 
	RAISE(FPSCR_OFC, FPSCR_OFE, FPE_FLTOVF);

	RAISE(FPSCR_IOC, FPSCR_IOE, FPE_FLTINV);



	if (si_code)

		vfp_raise_sigfpe(si_code, regs);

	return si_code;

}



/*
@@ -324,6 +350,8 @@ static u32 vfp_emulate_instruction(u32 inst, u32 fpscr, struct pt_regs *regs) 
static void VFP_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs)

{

	u32 fpscr, orig_fpscr, fpsid, exceptions;

	int si_code2 = 0;

	int si_code = 0;



	pr_debug("VFP: bounce: trigger %08x fpexc %08x\n", trigger, fpexc);
@@ -369,8 +397,8 @@ static void VFP_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs) 
		 * unallocated VFP instruction but with FPSCR.IXE set and not

		 * on VFP subarch 1.

		 */

		 vfp_raise_exceptions(VFP_EXCEPTION_ERROR, trigger, fpscr, regs);

		return;

		si_code = vfp_raise_exceptions(VFP_EXCEPTION_ERROR, trigger, fpscr);

		goto exit;

	}



	/*
@@ -394,14 +422,14 @@ static void VFP_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs) 
	 */

	exceptions = vfp_emulate_instruction(trigger, fpscr, regs);

	if (exceptions)

		vfp_raise_exceptions(exceptions, trigger, orig_fpscr, regs);

		si_code2 = vfp_raise_exceptions(exceptions, trigger, orig_fpscr);



	/*

	 * If there isn't a second FP instruction, exit now. Note that

	 * the FPEXC.FP2V bit is valid only if FPEXC.EX is 1.

	 */

	if ((fpexc & (FPEXC_EX | FPEXC_FP2V)) != (FPEXC_EX | FPEXC_FP2V))

		return;

		goto exit;



	/*

	 * The barrier() here prevents fpinst2 being read
@@ -413,7 +441,13 @@ static void VFP_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs) 
 emulate:

	exceptions = vfp_emulate_instruction(trigger, orig_fpscr, regs);

	if (exceptions)

		vfp_raise_exceptions(exceptions, trigger, orig_fpscr, regs);

		si_code = vfp_raise_exceptions(exceptions, trigger, orig_fpscr);

exit:

	vfp_state_release();

	if (si_code2)

		vfp_raise_sigfpe(si_code2, regs);

	if (si_code)

		vfp_raise_sigfpe(si_code, regs);

}



static void vfp_enable(void *unused)
@@ -512,11 +546,9 @@ static inline void vfp_pm_init(void) { } 
 */

void vfp_sync_hwstate(struct thread_info *thread)

{

	unsigned int cpu = get_cpu();



	local_bh_disable();

	vfp_state_hold();



	if (vfp_state_in_hw(cpu, thread)) {

	if (vfp_state_in_hw(raw_smp_processor_id(), thread)) {

		u32 fpexc = fmrx(FPEXC);



		/*
@@ -527,8 +559,7 @@ void vfp_sync_hwstate(struct thread_info *thread) 
		fmxr(FPEXC, fpexc);

	}



	local_bh_enable();

	put_cpu();

	vfp_state_release();

}



/* Ensure that the thread reloads the hardware VFP state on the next use. */
@@ -683,7 +714,7 @@ static int vfp_support_entry(struct pt_regs *regs, u32 trigger) 
	if (!user_mode(regs))

		return vfp_kmode_exception(regs, trigger);



	local_bh_disable();

	vfp_state_hold();

	fpexc = fmrx(FPEXC);



	/*
@@ -748,6 +779,7 @@ static int vfp_support_entry(struct pt_regs *regs, u32 trigger) 
		 * replay the instruction that trapped.

		 */

		fmxr(FPEXC, fpexc);

		vfp_state_release();

	} else {

		/* Check for synchronous or asynchronous exceptions */

		if (!(fpexc & (FPEXC_EX | FPEXC_DEX))) {
@@ -762,17 +794,17 @@ static int vfp_support_entry(struct pt_regs *regs, u32 trigger) 
			if (!(fpscr & FPSCR_IXE)) {

				if (!(fpscr & FPSCR_LENGTH_MASK)) {

					pr_debug("not VFP\n");

					local_bh_enable();

					vfp_state_release();

					return -ENOEXEC;

				}

				fpexc |= FPEXC_DEX;

			}

		}

bounce:		regs->ARM_pc += 4;

		/* VFP_bounce() will invoke vfp_state_release() */

		VFP_bounce(trigger, fpexc, regs);

	}



	local_bh_enable();

	return 0;

}
@@ -837,7 +869,7 @@ void kernel_neon_begin(void) 
	unsigned int cpu;

	u32 fpexc;



	local_bh_disable();

	vfp_state_hold();



	/*

	 * Kernel mode NEON is only allowed outside of hardirq context with
@@ -868,7 +900,7 @@ void kernel_neon_end(void) 
{

	/* Disable the NEON/VFP unit. */

	fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN);

	local_bh_enable();

	vfp_state_release();

}

EXPORT_SYMBOL(kernel_neon_end);

drivers/amba/bus.c

+6 −0
Original line number Diff line number Diff line
@@ -449,6 +449,12 @@ const struct bus_type amba_bustype = { 
};

EXPORT_SYMBOL_GPL(amba_bustype);



bool dev_is_amba(const struct device *dev)

{

	return dev->bus == &amba_bustype;

}

EXPORT_SYMBOL_GPL(dev_is_amba);



static int __init amba_init(void)

{

	return bus_register(&amba_bustype);

include/linux/amba/bus.h

+5 −0
Original line number Diff line number Diff line
@@ -121,6 +121,7 @@ extern const struct bus_type amba_bustype; 
#ifdef CONFIG_ARM_AMBA

int __amba_driver_register(struct amba_driver *, struct module *);

void amba_driver_unregister(struct amba_driver *);

bool dev_is_amba(const struct device *dev);

#else

static inline int __amba_driver_register(struct amba_driver *drv,

					 struct module *owner)
@@ -130,6 +131,10 @@ static inline int __amba_driver_register(struct amba_driver *drv, 
static inline void amba_driver_unregister(struct amba_driver *drv)

{

}

static inline bool dev_is_amba(const struct device *dev)

{

	return false;

}

#endif



struct amba_device *amba_device_alloc(const char *, resource_size_t, size_t);