The fix was already reviewed by Prashant and accepted by Rafael: https://git.kernel.org/cgit/linux/kernel/git/rafael/linux-pm.git/commit/?h=bleeding-edge&id=6ca595a70bc46e1a0eea3ee0681360f41555bfd9 Signed-off-by: Duc Dang <dhdang at apm.com> --- ...-Fix-lockdep-warning-when-request-PCC-cha.patch | 120 +++++++++++++++++++++ SPECS/kernel-aarch64.spec | 3 + 2 files changed, 123 insertions(+) create mode 100644 SOURCES/1028-mailbox-PCC-Fix-lockdep-warning-when-request-PCC-cha.patch diff --git a/SOURCES/1028-mailbox-PCC-Fix-lockdep-warning-when-request-PCC-cha.patch b/SOURCES/1028-mailbox-PCC-Fix-lockdep-warning-when-request-PCC-cha.patch new file mode 100644 index 0000000..9276390 --- /dev/null +++ b/SOURCES/1028-mailbox-PCC-Fix-lockdep-warning-when-request-PCC-cha.patch @@ -0,0 +1,120 @@ +From ba77f6beff28859afd0b57282012183684647d8a Mon Sep 17 00:00:00 2001 +From: Hoan Tran <hotran at apm.com> +Date: Mon, 14 Nov 2016 11:19:02 -0800 +Subject: [PATCH] mailbox: PCC: Fix lockdep warning when request PCC channel + +This patch fixes the lockdep warning below + +DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags)) +------------[ cut here ]------------ +WARNING: CPU: 1 PID: 1 at linux-next/kernel/locking/lockdep.c:2876 lockdep_trace_alloc+0xe0/0xf0 + Modules linked in: + + CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.8.0-11756-g86c5152 #46 +... + Call trace: + Exception stack(0xffff8007da837890 to 0xffff8007da8379c0) + 7880: ffff8007da834000 0001000000000000 + 78a0: ffff8007da837a70 ffff0000081111a0 00000000600000c5 000000000000003d + 78c0: 9374bc6a7f3c7832 0000000000381878 ffff000009db7ab8 000000000000002f + 78e0: ffff00000811aabc ffff000008be2548 ffff8007da837990 ffff00000811adf8 + 7900: ffff8007da834000 00000000024080c0 00000000000000c0 ffff000009021000 + 7920: 0000000000000000 0000000000000000 ffff000008c8f7c8 ffff8007da579810 + 7940: 000000000000002f ffff8007da858000 0000000000000000 0000000000000001 + 7960: 0000000000000001 0000000000000000 ffff00000811a468 0000000000000002 + 7980: 656c62617369645f 0000000000038187 00000000000000ee ffff8007da837850 + 79a0: ffff000009db50c0 ffff000009db569d 0000000000000006 ffff000089db568f + [<ffff0000081111a0>] lockdep_trace_alloc+0xe0/0xf0 + [<ffff0000081f4950>] __kmalloc_track_caller+0x50/0x250 + [<ffff00000857c088>] devres_alloc_node+0x28/0x60 + [<ffff0000081220e0>] devm_request_threaded_irq+0x50/0xe0 + [<ffff0000087e6220>] pcc_mbox_request_channel+0x110/0x170 + [<ffff0000084b2660>] acpi_cppc_processor_probe+0x264/0x414 + [<ffff0000084ae9f4>] __acpi_processor_start+0x28/0xa0 + [<ffff0000084aeab0>] acpi_processor_start+0x44/0x54 + [<ffff00000857897c>] driver_probe_device+0x1fc/0x2b0 + [<ffff000008578ae4>] __driver_attach+0xb4/0xc0 + [<ffff00000857683c>] bus_for_each_dev+0x5c/0xa0 + [<ffff000008578110>] driver_attach+0x20/0x30 + [<ffff000008577c20>] bus_add_driver+0x110/0x230 + [<ffff000008579320>] driver_register+0x60/0x100 + [<ffff000008d478b8>] acpi_processor_driver_init+0x2c/0xb0 + [<ffff000008083168>] do_one_initcall+0x38/0x130 + [<ffff000008d20d6c>] kernel_init_freeable+0x210/0x2b4 + [<ffff000008945d90>] kernel_init+0x10/0x110 + [<ffff000008082e80>] ret_from_fork+0x10/0x50 + +It's because the spinlock inside pcc_mbox_request_channel() is +kept too long. This patch releases spinlock before request_irq() +and free_irq() to fix this issue as spinlock is only needed to +protect the channel data. + +Signed-off-by: Hoan Tran <hotran at apm.com> +Reviewed-by: Prashanth Prakash <pprakash at codeaurora.org> +Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com> +--- + drivers/mailbox/pcc.c | 13 +++++++------ + 1 file changed, 7 insertions(+), 6 deletions(-) + +diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c +index c98bd94..fb594ed 100644 +--- a/drivers/mailbox/pcc.c ++++ b/drivers/mailbox/pcc.c +@@ -65,6 +65,7 @@ + #include <linux/mailbox_controller.h> + #include <linux/mailbox_client.h> + #include <linux/io-64-nonatomic-lo-hi.h> ++#include <acpi/pcc.h> + + #include "mailbox.h" + +@@ -267,6 +268,8 @@ struct mbox_chan *pcc_mbox_request_channel(struct mbox_client *cl, + if (chan->txdone_method == TXDONE_BY_POLL && cl->knows_txdone) + chan->txdone_method |= TXDONE_BY_ACK; + ++ spin_unlock_irqrestore(&chan->lock, flags); ++ + if (pcc_doorbell_irq[subspace_id] > 0) { + int rc; + +@@ -275,12 +278,11 @@ struct mbox_chan *pcc_mbox_request_channel(struct mbox_client *cl, + if (unlikely(rc)) { + dev_err(dev, "failed to register PCC interrupt %d\n", + pcc_doorbell_irq[subspace_id]); ++ pcc_mbox_free_channel(chan); + chan = ERR_PTR(rc); + } + } + +- spin_unlock_irqrestore(&chan->lock, flags); +- + return chan; + } + EXPORT_SYMBOL_GPL(pcc_mbox_request_channel); +@@ -304,20 +306,19 @@ void pcc_mbox_free_channel(struct mbox_chan *chan) + return; + } + ++ if (pcc_doorbell_irq[id] > 0) ++ devm_free_irq(chan->mbox->dev, pcc_doorbell_irq[id], chan); ++ + spin_lock_irqsave(&chan->lock, flags); + chan->cl = NULL; + chan->active_req = NULL; + if (chan->txdone_method == (TXDONE_BY_POLL | TXDONE_BY_ACK)) + chan->txdone_method = TXDONE_BY_POLL; + +- if (pcc_doorbell_irq[id] > 0) +- devm_free_irq(chan->mbox->dev, pcc_doorbell_irq[id], chan); +- + spin_unlock_irqrestore(&chan->lock, flags); + } + EXPORT_SYMBOL_GPL(pcc_mbox_free_channel); + +- + /** + * pcc_send_data - Called from Mailbox Controller code. Used + * here only to ring the channel doorbell. The PCC client +-- +1.8.3.1 + diff --git a/SPECS/kernel-aarch64.spec b/SPECS/kernel-aarch64.spec index 6e7950b..b9596d5 100644 --- a/SPECS/kernel-aarch64.spec +++ b/SPECS/kernel-aarch64.spec @@ -352,6 +352,7 @@ Patch1024: 1024-arm64-efi-esrt-add-missing-call-to-efi_esrt_init.patch Patch1025: 1025-efi-esrt-Don-t-preformat-name.patch Patch1026: 1026-efi-esrt-Use-efi_mem_reserve-and-avoid-a-kmalloc.patch Patch1027: 1027-efi-esrt-Use-memremap-not-ioremap-to-access-ESRT-tab.patch +Patch1028: 1028-mailbox-PCC-Fix-lockdep-warning-when-request-PCC-cha.patch # QDF2400 Patches Patch4000: 4000-arm64-Define-Qualcomm-Technologies-ARMv8-CPU.patch @@ -714,6 +715,7 @@ git am %{PATCH1024} git am %{PATCH1025} git am %{PATCH1026} git am %{PATCH1027} +git am %{PATCH1028} # Apply QDF2400 patches git am %{PATCH4000} @@ -1493,6 +1495,7 @@ fi %changelog * Thu Nov 17 2016 Duc Dang <dhdang at apm.com> [4.5.0-18.el7] +- Integrate upstream fix for a lockdep warning when request PCC channel - Backport upstream patches to support fwupdate - Integrate upstream patch to add interrupt support for X-Gene Standby GPIO -- 1.8.3.1