#ifndef _PKEYS_HELPER_H
#define _PKEYS_HELPER_H
#define _GNU_SOURCE
#include <string.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include <signal.h>
#include <assert.h>
#include <stdlib.h>
#include <ucontext.h>
#include <sys/mman.h>

#define NR_PKEYS 16
#define PKRU_BITS_PER_PKEY 2

#ifndef DEBUG_LEVEL
#define DEBUG_LEVEL 0
#endif
#define DPRINT_IN_SIGNAL_BUF_SIZE 4096
extern int dprint_in_signal;
extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
static inline void sigsafe_printf(const char *format, ...)
{
	va_list ap;

	va_start(ap, format);
	if (!dprint_in_signal) {
		vprintf(format, ap);
	} else {
		int len = vsnprintf(dprint_in_signal_buffer,
				    DPRINT_IN_SIGNAL_BUF_SIZE,
				    format, ap);
		/*
		 * len is amount that would have been printed,
		 * but actual write is truncated at BUF_SIZE.
		 */
		if (len > DPRINT_IN_SIGNAL_BUF_SIZE)
			len = DPRINT_IN_SIGNAL_BUF_SIZE;
		write(1, dprint_in_signal_buffer, len);
	}
	va_end(ap);
}
#define dprintf_level(level, args...) do {	\
	if (level <= DEBUG_LEVEL)		\
		sigsafe_printf(args);		\
	fflush(NULL);				\
} while (0)
#define dprintf0(args...) dprintf_level(0, args)
#define dprintf1(args...) dprintf_level(1, args)
#define dprintf2(args...) dprintf_level(2, args)
#define dprintf3(args...) dprintf_level(3, args)
#define dprintf4(args...) dprintf_level(4, args)

extern unsigned int shadow_pkru;
static inline unsigned int __rdpkru(void)
{
	unsigned int eax, edx;
	unsigned int ecx = 0;
	unsigned int pkru;

	asm volatile(".byte 0x0f,0x01,0xee\n\t"
		     : "=a" (eax), "=d" (edx)
		     : "c" (ecx));
	pkru = eax;
	return pkru;
}

static inline unsigned int _rdpkru(int line)
{
	unsigned int pkru = __rdpkru();

	dprintf4("rdpkru(line=%d) pkru: %x shadow: %x\n",
			line, pkru, shadow_pkru);
	assert(pkru == shadow_pkru);

	return pkru;
}

#define rdpkru() _rdpkru(__LINE__)

static inline void __wrpkru(unsigned int pkru)
{
	unsigned int eax = pkru;
	unsigned int ecx = 0;
	unsigned int edx = 0;

	dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
	asm volatile(".byte 0x0f,0x01,0xef\n\t"
		     : : "a" (eax), "c" (ecx), "d" (edx));
	assert(pkru == __rdpkru());
}

static inline void wrpkru(unsigned int pkru)
{
	dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
	/* will do the shadow check for us: */
	rdpkru();
	__wrpkru(pkru);
	shadow_pkru = pkru;
	dprintf4("%s(%08x) pkru: %08x\n", __func__, pkru, __rdpkru());
}

/*
 * These are technically racy. since something could
 * change PKRU between the read and the write.
 */
static inline void __pkey_access_allow(int pkey, int do_allow)
{
	unsigned int pkru = rdpkru();
	int bit = pkey * 2;

	if (do_allow)
		pkru &= (1<<bit);
	else
		pkru |= (1<<bit);

	dprintf4("pkru now: %08x\n", rdpkru());
	wrpkru(pkru);
}

static inline void __pkey_write_allow(int pkey, int do_allow_write)
{
	long pkru = rdpkru();
	int bit = pkey * 2 + 1;

	if (do_allow_write)
		pkru &= (1<<bit);
	else
		pkru |= (1<<bit);

	wrpkru(pkru);
	dprintf4("pkru now: %08x\n", rdpkru());
}

#define PROT_PKEY0     0x10            /* protection key value (bit 0) */
#define PROT_PKEY1     0x20            /* protection key value (bit 1) */
#define PROT_PKEY2     0x40            /* protection key value (bit 2) */
#define PROT_PKEY3     0x80            /* protection key value (bit 3) */

#define PAGE_SIZE 4096
#define MB	(1<<20)

static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
		unsigned int *ecx, unsigned int *edx)
{
	/* ecx is often an input as well as an output. */
	asm volatile(
		"cpuid;"
		: "=a" (*eax),
		  "=b" (*ebx),
		  "=c" (*ecx),
		  "=d" (*edx)
		: "0" (*eax), "2" (*ecx));
}

/* Intel-defined CPU features, CPUID level 0x00000007:0 (ecx) */
#define X86_FEATURE_PKU        (1<<3) /* Protection Keys for Userspace */
#define X86_FEATURE_OSPKE      (1<<4) /* OS Protection Keys Enable */

static inline int cpu_has_pku(void)
{
	unsigned int eax;
	unsigned int ebx;
	unsigned int ecx;
	unsigned int edx;

	eax = 0x7;
	ecx = 0x0;
	__cpuid(&eax, &ebx, &ecx, &edx);

	if (!(ecx & X86_FEATURE_PKU)) {
		dprintf2("cpu does not have PKU\n");
		return 0;
	}
	if (!(ecx & X86_FEATURE_OSPKE)) {
		dprintf2("cpu does not have OSPKE\n");
		return 0;
	}
	return 1;
}

#define XSTATE_PKRU_BIT	(9)
#define XSTATE_PKRU	0x200

int pkru_xstate_offset(void)
{
	unsigned int eax;
	unsigned int ebx;
	unsigned int ecx;
	unsigned int edx;
	int xstate_offset;
	int xstate_size;
	unsigned long XSTATE_CPUID = 0xd;
	int leaf;

	/* assume that XSTATE_PKRU is set in XCR0 */
	leaf = XSTATE_PKRU_BIT;
	{
		eax = XSTATE_CPUID;
		ecx = leaf;
		__cpuid(&eax, &ebx, &ecx, &edx);

		if (leaf == XSTATE_PKRU_BIT) {
			xstate_offset = ebx;
			xstate_size = eax;
		}
	}

	if (xstate_size == 0) {
		printf("could not find size/offset of PKRU in xsave state\n");
		return 0;
	}

	return xstate_offset;
}

#endif /* _PKEYS_HELPER_H */
36f'>54791b276b4000b307339f269d3bf7db877d536f</a> (<a href='/cgit.cgi/linux/net-next.git/patch/include/acpi/ghes.h?id=54791b276b4000b307339f269d3bf7db877d536f'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=54791b276b4000b307339f269d3bf7db877d536f'>1c2616bd373ce5ea28aac2a53e32f5b5834901ce</a> /<a href='/cgit.cgi/linux/net-next.git/tree/include/acpi/ghes.h?id=54791b276b4000b307339f269d3bf7db877d536f'>include/acpi/ghes.h</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/acpi/ghes.h?id=5d0e7705774dd412a465896d08d59a81a345c1e4'>5d0e7705774dd412a465896d08d59a81a345c1e4</a> (<a href='/cgit.cgi/linux/net-next.git/diff/include/acpi/ghes.h?id=54791b276b4000b307339f269d3bf7db877d536f&amp;id2=5d0e7705774dd412a465896d08d59a81a345c1e4'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/acpi/ghes.h?id=047487241ff59374fded8c477f21453681f5995c'>047487241ff59374fded8c477f21453681f5995c</a> (<a href='/cgit.cgi/linux/net-next.git/diff/include/acpi/ghes.h?id=54791b276b4000b307339f269d3bf7db877d536f&amp;id2=047487241ff59374fded8c477f21453681f5995c'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge branch 'sparc64-non-resumable-user-error-recovery'</div><div class='commit-msg'>Liam R. Howlett says:

====================
sparc64: Recover from userspace non-resumable PIO &amp; MEM errors

A non-resumable error from userspace is able to cause a kernel panic or trap
loop due to the setup and handling of the queued traps once in the kernel.
This patch series addresses both of these issues.

The queues are fixed by simply zeroing the memory before use.

PIO errors from userspace will result in a SIGBUS being sent to the user
process.

The MEM errors form userspace will result in a SIGKILL and also cause the
offending pages to be claimed so they are no longer used in future tasks.
SIGKILL is used to ensure that the process does not try to coredump and result
in an attempt to read the memory again from within kernel space.  Although
there is a HV call to scrub the memory (mem_scrub), there is no easy way to
guarantee that the real memory address(es) are not used by other tasks.
Clearing the error with mem_scrub would zero the memory and cause the other
processes to proceed with bad data.

The handling of other non-resumable errors remain unchanged and will cause a
panic.
====================

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=54791b276b4000b307339f269d3bf7db877d536f'>Diffstat</a> (limited to 'include/acpi/ghes.h')</div><table summary='diffstat' class='diffstat'>