This is a note to let you know that I've just added the patch titled ACPI / EC: Add support to disallow QR_EC to be issued before completing previous QR_EC to the 3.16-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: acpi-ec-add-support-to-disallow-qr_ec-to-be-issued-before-completing-previous-qr_ec.patch and it can be found in the queue-3.16 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 558e4736f2e1b0e6323adf7a5e4df77ed6cfc1a4 Mon Sep 17 00:00:00 2001 From: Lv Zheng <lv.zheng@xxxxxxxxx> Date: Thu, 21 Aug 2014 14:41:26 +0800 Subject: ACPI / EC: Add support to disallow QR_EC to be issued before completing previous QR_EC From: Lv Zheng <lv.zheng@xxxxxxxxx> commit 558e4736f2e1b0e6323adf7a5e4df77ed6cfc1a4 upstream. There is platform refusing to respond QR_EC when SCI_EVT isn't set which is Acer Aspire V5-573G. By disallowing QR_EC to be issued before the previous one has been completed we are able to reduce the possibilities to trigger issues on such platforms. Note that this fix can only reduce the occurrence rate of this issue, but this issue may still occur when such a platform doesn't clear SCI_EVT before or immediately after completing the previous QR_EC transaction. This patch cannot fix the CLEAR_ON_RESUME quirk which also relies on the assumption that the platforms are able to respond even when SCI_EVT isn't set. But this patch is still useful as it can help to reduce the number of scheduled QR_EC work items. Link: https://bugzilla.kernel.org/show_bug.cgi?id=82611 Reported-and-tested-by: Alexander Mezin <mezin.alexander@xxxxxxxxx> Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/acpi/ec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -303,11 +303,11 @@ static int acpi_ec_transaction_unlocked( /* following two actions should be kept atomic */ ec->curr = t; start_transaction(ec); - if (ec->curr->command == ACPI_EC_COMMAND_QUERY) - clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); spin_unlock_irqrestore(&ec->lock, tmp); ret = ec_poll(ec); spin_lock_irqsave(&ec->lock, tmp); + if (ec->curr->command == ACPI_EC_COMMAND_QUERY) + clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); ec->curr = NULL; spin_unlock_irqrestore(&ec->lock, tmp); return ret; Patches currently in stable-queue which might be from lv.zheng@xxxxxxxxx are queue-3.16/acpica-utilities-fix-memory-leak-in-acpi_ut_copy_iobject_to_iobject.patch queue-3.16/acpica-namespace-properly-null-terminate-objects-detached-from-a-namespace-node.patch queue-3.16/acpi-ec-add-support-to-disallow-qr_ec-to-be-issued-when-sci_evt-isn-t-set.patch queue-3.16/acpi-ec-add-support-to-disallow-qr_ec-to-be-issued-before-completing-previous-qr_ec.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html