[This is backport for 5.4 of 29daf869cbab69088fe1755d9dd224e99ba78b56]
The kernel expects pte_young() to work regardless of CONFIG_SWAP.
Make sure a minor fault is taken to set _PAGE_ACCESSED when it
is not already set, regardless of the selection of CONFIG_SWAP.
This adds at least 3 instructions to the TLB miss exception
handlers fast path. Following patch will reduce this overhead.
Also update the rotation instruction to the correct number of bits
to reflect all changes done to _PAGE_ACCESSED over time.
Fixes: d069cb4373fe ("powerpc/8xx: Don't touch ACCESSED when no SWAP.")
Fixes: 5f356497c384 ("powerpc/8xx: remove unused _PAGE_WRITETHRU")
Fixes: e0a8e0d90a9f ("powerpc/8xx: Handle PAGE_USER via APG bits")
Fixes: 5b2753fc3e8a ("powerpc/8xx: Implementation of PAGE_EXEC")
Fixes: a891c43b97d3 ("powerpc/8xx: Prepare handlers for _PAGE_HUGE for 512k pages.")
Cc: stable(a)vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy(a)csgroup.eu>
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
Link: https://lore.kernel.org/r/af834e8a0f1fa97bfae65664950f0984a70c4750.16024928…
---
arch/powerpc/kernel/head_8xx.S | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 98d8b6832fcb..f6428b90a6c7 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -229,9 +229,7 @@ SystemCall:
InstructionTLBMiss:
mtspr SPRN_SPRG_SCRATCH0, r10
-#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_SWAP)
mtspr SPRN_SPRG_SCRATCH1, r11
-#endif
/* If we are faulting a kernel address, we have to use the
* kernel page tables.
@@ -278,11 +276,9 @@ InstructionTLBMiss:
#ifdef ITLB_MISS_KERNEL
mtcr r11
#endif
-#ifdef CONFIG_SWAP
- rlwinm r11, r10, 32-5, _PAGE_PRESENT
+ rlwinm r11, r10, 32-7, _PAGE_PRESENT
and r11, r11, r10
rlwimi r10, r11, 0, _PAGE_PRESENT
-#endif
/* The Linux PTE won't go exactly into the MMU TLB.
* Software indicator bits 20 and 23 must be clear.
* Software indicator bits 22, 24, 25, 26, and 27 must be
@@ -296,9 +292,7 @@ InstructionTLBMiss:
/* Restore registers */
0: mfspr r10, SPRN_SPRG_SCRATCH0
-#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_SWAP)
mfspr r11, SPRN_SPRG_SCRATCH1
-#endif
rfi
patch_site 0b, patch__itlbmiss_exit_1
@@ -308,9 +302,7 @@ InstructionTLBMiss:
addi r10, r10, 1
stw r10, (itlb_miss_counter - PAGE_OFFSET)@l(0)
mfspr r10, SPRN_SPRG_SCRATCH0
-#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_SWAP)
mfspr r11, SPRN_SPRG_SCRATCH1
-#endif
rfi
#endif
@@ -394,11 +386,9 @@ DataStoreTLBMiss:
* r11 = ((r10 & PRESENT) & ((r10 & ACCESSED) >> 5));
* r10 = (r10 & ~PRESENT) | r11;
*/
-#ifdef CONFIG_SWAP
- rlwinm r11, r10, 32-5, _PAGE_PRESENT
+ rlwinm r11, r10, 32-7, _PAGE_PRESENT
and r11, r11, r10
rlwimi r10, r11, 0, _PAGE_PRESENT
-#endif
/* The Linux PTE won't go exactly into the MMU TLB.
* Software indicator bits 24, 25, 26, and 27 must be
* set. All other Linux PTE bits control the behavior
--
2.25.0
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 1b02d9e770cd7087f34c743f85ccf5ea8372b047 Mon Sep 17 00:00:00 2001
From: Bartosz Golaszewski <bgolaszewski(a)baylibre.com>
Date: Tue, 8 Sep 2020 15:07:49 +0200
Subject: [PATCH] gpio: mockup: fix resource leak in error path
If the module init function fails after creating the debugs directory,
it's never removed. Add proper cleanup calls to avoid this resource
leak.
Fixes: 9202ba2397d1 ("gpio: mockup: implement event injecting over debugfs")
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski(a)baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko(a)linux.intel.com>
diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
index bc345185db26..1652897fdf90 100644
--- a/drivers/gpio/gpio-mockup.c
+++ b/drivers/gpio/gpio-mockup.c
@@ -552,6 +552,7 @@ static int __init gpio_mockup_init(void)
err = platform_driver_register(&gpio_mockup_driver);
if (err) {
gpio_mockup_err("error registering platform driver\n");
+ debugfs_remove_recursive(gpio_mockup_dbg_dir);
return err;
}
@@ -582,6 +583,7 @@ static int __init gpio_mockup_init(void)
gpio_mockup_err("error registering device");
platform_driver_unregister(&gpio_mockup_driver);
gpio_mockup_unregister_pdevs();
+ debugfs_remove_recursive(gpio_mockup_dbg_dir);
return PTR_ERR(pdev);
}
Hi Greg, Sasha,
This was missing in 4.4-stable. It was easier to backport than picking
all the other commits needed to aply it cleanly. It has been manually
backported with an extra label for goto. I will prefer an Ack from
Wolfram or Krzysztof or Oleksij before you add it to your queue.
--
Regards
Sudip