[FS#1242] SATA broken on kernel 4.9 on mt7621

[LEDE Bugs]

The following task has a new comment added:

FS#1242 - SATA broken on kernel 4.9 on mt7621
User who did this - neheb (neheb)

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Yeah I did a diff between config-4.4 and config-4.9 and removed newly introduced CONFIGs. It worked. I have firmware on 4.9 that does not show this issue. Unfortunately, I lost the exact config.

I'm currently testing a new one but unfortunately, this testing of bad kernels destroyed my btrfs array. Now I need to rebuild it...

diff --git a/target/linux/ramips/mt7621/config-4.9 b/target/linux/ramips/mt7621/config-4.9
index 0ea6798..b3c8afc 100644
--- a/target/linux/ramips/mt7621/config-4.9
+++ b/target/linux/ramips/mt7621/config-4.9
@@ -67,7 +67,6 @@ CONFIG_GENERIC_CLOCKEVENTS=y
 CONFIG_GENERIC_CMOS_UPDATE=y
 CONFIG_GENERIC_IO=y
 CONFIG_GENERIC_IRQ_CHIP=y
-CONFIG_GENERIC_IRQ_IPI=y
 CONFIG_GENERIC_IRQ_SHOW=y
 CONFIG_GENERIC_PCI_IOMAP=y
 CONFIG_GENERIC_SCHED_CLOCK=y
@@ -105,7 +104,6 @@ CONFIG_HAVE_FUNCTION_GRAPH_TRACER=y
 CONFIG_HAVE_FUNCTION_TRACER=y
 CONFIG_HAVE_GENERIC_DMA_COHERENT=y
 CONFIG_HAVE_IDE=y
-CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK=y
 CONFIG_HAVE_IRQ_TIME_ACCOUNTING=y
 CONFIG_HAVE_KVM=y
 CONFIG_HAVE_LATENCYTOP_SUPPORT=y
@@ -127,7 +125,6 @@ CONFIG_I2C_MT7621=y
 CONFIG_INITRAMFS_SOURCE=""
 CONFIG_IRQCHIP=y
 CONFIG_IRQ_DOMAIN=y
-CONFIG_IRQ_DOMAIN_HIERARCHY=y
 CONFIG_IRQ_FORCED_THREADING=y
 CONFIG_IRQ_MIPS_CPU=y
 CONFIG_IRQ_WORK=y

and yes, I attributed the error to the wrong CONFIG.
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=1242#comment4123