From: Zhao Yakui <yakui.zhao@xxxxxxxxx> On some broken BIOS the ACPI object in EC _REG method can't be found in ACPI namespace, which causes that the status code of AE_NOT_FOUND is returned by the EC _REG object. In such case the EC device can't be initialized correctly, which causes that battery/AC adapter can't work normally. As the EC address space handler is not removed and the memory pointed by its input argument is already free, sometimes the kernel will also be panic when EC internal register is still accessed. But the windows can work well on such broken BIOS. Maybe it will be reasonable that OS ignores the AE_NOT_FOUND error returned by the EC _REG object and continues to initialize EC device on some broken BIOS. For example: the ACPI object in EC _REG method can't be found and status error code is AE_NOT_FOUND. http://bugzilla.kernel.org/show_bug.cgi?id=8953 http://bugzilla.kernel.org/show_bug.cgi?id=10237 lenb: we may find a more general solution to this in the future. Signed-off-by: Zhao Yakui <yakui.zhao@xxxxxxxxx> Signed-off-by: Lin Ming <ming.m.lin@xxxxxxxxx> Signed-off-by: Len Brown <len.brown@xxxxxxxxx> --- drivers/acpi/ec.c | 15 +++++++++++++-- 1 files changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 13593f9..4c00428 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -862,8 +862,19 @@ static int ec_install_handlers(struct acpi_ec *ec) &acpi_ec_space_handler, NULL, ec); if (ACPI_FAILURE(status)) { - acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler); - return -ENODEV; + if (status == AE_NOT_FOUND) { + /* + * Maybe OS fails in evaluating the _REG object. + * The AE_NOT_FOUND error will be ignored and OS + * continue to initialize EC. + */ + printk(KERN_ERR "Fail in evaluating the _REG object" + " of EC device. Broken bios is suspected.\n"); + } else { + acpi_remove_gpe_handler(NULL, ec->gpe, + &acpi_ec_gpe_handler); + return -ENODEV; + } } ec->handlers_installed = 1; -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
