/*
* There are multiple 16-bit CRC polynomials in common use, but this is
* *the* standard CRC-32 polynomial, first popularized by Ethernet.
* x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x^1+x^0
*/
#define CRCPOLY_LE 0xedb88320
#define CRCPOLY_BE 0x04c11db7
/*
* This is the CRC32c polynomial, as outlined by Castagnoli.
* x^32+x^28+x^27+x^26+x^25+x^23+x^22+x^20+x^19+x^18+x^14+x^13+x^11+x^10+x^9+
* x^8+x^6+x^0
*/
#define CRC32C_POLY_LE 0x82F63B78
/* Try to choose an implementation variant via Kconfig */
#ifdef CONFIG_CRC32_SLICEBY8
# define CRC_LE_BITS 64
# define CRC_BE_BITS 64
#endif
#ifdef CONFIG_CRC32_SLICEBY4
# define CRC_LE_BITS 32
# define CRC_BE_BITS 32
#endif
#ifdef CONFIG_CRC32_SARWATE
# define CRC_LE_BITS 8
# define CRC_BE_BITS 8
#endif
#ifdef CONFIG_CRC32_BIT
# define CRC_LE_BITS 1
# define CRC_BE_BITS 1
#endif
/*
* How many bits at a time to use. Valid values are 1, 2, 4, 8, 32 and 64.
* For less performance-sensitive, use 4 or 8 to save table size.
* For larger systems choose same as CPU architecture as default.
* This works well on X86_64, SPARC64 systems. This may require some
* elaboration after experiments with other architectures.
*/
#ifndef CRC_LE_BITS
# ifdef CONFIG_64BIT
# define CRC_LE_BITS 64
# else
# define CRC_LE_BITS 32
# endif
#endif
#ifndef CRC_BE_BITS
# ifdef CONFIG_64BIT
# define CRC_BE_BITS 64
# else
# define CRC_BE_BITS 32
# endif
#endif
/*
* Little-endian CRC computation. Used with serial bit streams sent
* lsbit-first. Be sure to use cpu_to_le32() to append the computed CRC.
*/
#if CRC_LE_BITS > 64 || CRC_LE_BITS < 1 || CRC_LE_BITS == 16 || \
CRC_LE_BITS & CRC_LE_BITS-1
# error "CRC_LE_BITS must be one of {1, 2, 4, 8, 32, 64}"
#endif
/*
* Big-endian CRC computation. Used with serial bit streams sent
* msbit-first. Be sure to use cpu_to_be32() to append the computed CRC.
*/
#if CRC_BE_BITS > 64 || CRC_BE_BITS < 1 || CRC_BE_BITS == 16 || \
CRC_BE_BITS & CRC_BE_BITS-1
# error "CRC_BE_BITS must be one of {1, 2, 4, 8, 32, 64}"
#endif
i/linux/net-next.git/commit/sound/pci/ctxfi/cthw20k1.c?h=nds-private-remove&id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>commitdiff
x86/mce: Make timer handling more robust
Erik reported that on a preproduction hardware a CMCI storm triggers the
BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is
started by the CMCI logic before the MCE CPU hotplug callback starts the
timer with add_timer_on(). So the timer is already queued which triggers
the BUG.
Using add_timer_on() is pretty pointless in this code because the timer is
strictlty per CPU, initialized as pinned and all operations which arm the
timer happen on the CPU to which the timer belongs.
Simplify the whole machinery by using mod_timer() instead of add_timer_on()
which avoids the problem because mod_timer() can handle already queued
timers. Use __start_timer() everywhere so the earliest armed expiry time is
preserved.
Reported-by: Erik Veijola <erik.veijola@intel.com>
Tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>