The patch titled acpi: check _PSS invalidation when BIOS report _PSS with 0x80000000 has been added to the -mm tree. Its filename is acpi-check-_pss-invalidation-when-bios-report-_pss-with-all-0x80000000.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: acpi: check _PSS invalidation when BIOS report _PSS with 0x80000000 From: youquan_song@xxxxxxxxxxxxxxx When cpu frequencey scaling is disabled, some BIOSes report _PSS with all 0x80000000. If the kernel treats this case as valid, the kernel will boot crash when load cpufreq govenors. So in order to cover more buggy BIOSs, the patch just check _PSS core frequency invalidation. Signed-off-by: Youquan, Song <youquan.song@xxxxxxxxx> Signed-off-by: Pallipadi, Venkatesh <venkatesh.pallipadi@xxxxxxxxx> Cc: Len Brown <lenb@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/acpi/processor_perflib.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff -puN drivers/acpi/processor_perflib.c~acpi-check-_pss-invalidation-when-bios-report-_pss-with-all-0x80000000 drivers/acpi/processor_perflib.c --- a/drivers/acpi/processor_perflib.c~acpi-check-_pss-invalidation-when-bios-report-_pss-with-all-0x80000000 +++ a/drivers/acpi/processor_perflib.c @@ -50,6 +50,7 @@ #define ACPI_PROCESSOR_CLASS "processor" #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance" #define _COMPONENT ACPI_PROCESSOR_COMPONENT +#define ACPI_PROCESSOR_PSS_INVALID 0x80000000 ACPI_MODULE_NAME("processor_perflib"); static DEFINE_MUTEX(performance_mutex); @@ -324,6 +325,14 @@ static int acpi_processor_get_performanc kfree(pr->performance->states); goto end; } + + if (px->core_frequency == ACPI_PROCESSOR_PSS_INVALID) { + printk(KERN_ERR PREFIX + "P-states disabled in the BIOS\n"); + result = -EFAULT; + kfree(pr->performance->states); + goto end; + } } end: _ Patches currently in -mm which might be from youquan.song@xxxxxxxxx are acpi-check-_pss-invalidation-when-bios-report-_pss-with-all-0x80000000.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html