Re: [PASEMI] Nemo board doesn't boot anymore after the commit "powerpc/book3s64/pkeys: Simplify pkey disable branch"

Hello Aneesh,

The Nemo board boots with your patch but unfortunately I don't see any 
boot messages anymore.

Please find attached the kernel config.

Thanks,
Christian


On 09 August 2020 at 5:49 pm, Christian Zigotzky wrote:

Hello Aneesh,

Many thanks for your fast response and thanks a lot for your patch!
I will patch and compile a new git kernel tomorrow. I am looking forward to the result.

Have a nice day!

Cheers,
Christian

quoted

On 9. Aug 2020, at 17:11, Aneesh Kumar K.V [off-list ref] wrote:

"Aneesh Kumar K.V" [off-list ref] writes:

quoted

quoted

On 8/9/20 8:04 PM, Aneesh Kumar K.V wrote:
On 8/9/20 7:42 PM, Christian Zigotzky wrote:

quoted

Hello,

The Nemo board (A-EON AmigaOne X1000) [1] doesn't start with the
latest Git kernel anymore after the commit "powerpc/book3s64/pkeys:
Simplify pkey disable branch" [2].

I bisected today [3].

Result: powerpc/book3s64/pkeys: Simplify pkey disable branch
(a4678d4b477c3d2901f101986ca01406f3b7eaea) [2] is the first bad commit.

Unfortunately I wasn't able to revert the first bad commit. The first
bad commit depends on many other commits, which unfortunately I don't
know. I tried to remove the modifications of the files from the first
bad commit but without any success. There are just too many dependencies.

Additionally I reverted the commit "selftests/powerpc: Fix pkey
syscall redefinitions" [4] and compiled a new kernel but without any
success.

Could you please check the first bad commit?

Thanks,
Christian

Can you share a successful boot log of the system so that i can double
check the cpu_feature and mmu_feature reported ? I am looking for
details similar to below.

[    0.000000] cpu_features      = 0x0001c07f8f5f91a7
[    0.000000]   possible        = 0x0001fbffcf5fb1a7
[    0.000000]   always          = 0x00000003800081a1
[    0.000000] cpu_user_features = 0xdc0065c2 0xefe00000
[    0.000000] mmu_features      = 0x7c006001
[    0.000000] firmware_features = 0x0000001fc45bfc57
[    0.000000] vmalloc start     = 0xc008000000000000
[    0.000000] IO start          = 0xc00a000000000000
[    0.000000] vmemmap start     = 0xc00c000000000000


IIUC this is P5+? (ISA 2.04). On that pkey should be marked disabled via

static int scan_pkey_feature(void)
{
     int ret;
     int pkeys_total = 0;

     ....

     /*
      * Only P7 and above supports SPRN_AMR update with MSR[PR] = 1
      */
     if (!early_cpu_has_feature(CPU_FTR_ARCH_206))
         return 0;


}

Can you boot with CONFIG_PPC_MEM_KEYS=n ?

Can you try this change on top of master?


modified   arch/powerpc/mm/book3s64/pkeys.c

@@ -215,10 +215,6 @@ void __init pkey_early_init_devtree(void)

      pr_info("Enabling pkeys with max key count %d\n", num_pkey);
  out:
-    /*
-     * Setup uamor on boot cpu
-     */
-    mtspr(SPRN_UAMOR, default_uamor);

      return;
  }

Full patch with better description.

commit 919a177bcdaf1eaeaeecc0d0f50a688629d7b5df
Author: Aneesh Kumar K.V [off-list ref]
Date:   Sun Aug 9 20:37:38 2020 +0530

    powerpc/pkeys: Fix boot failures with Nemo board (A-EON AmigaOne X1000)

    On p6 and before we should avoid updating UAMOR SPRN. This resulted
    in boot failure on Nemo board.

    Fixes: 269e829f48a0 ("powerpc/book3s64/pkey: Disable pkey on POWER6 and before")
    Reported-by: Christian Zigotzky [off-list ref]
    Signed-off-by: Aneesh Kumar K.V [off-list ref]

diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 69a6b87f2bb4..b1d091a97611 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c

@@ -73,12 +73,6 @@ static int scan_pkey_feature(void)
    if (early_radix_enabled())
        return 0;

-    /*
-     * Only P7 and above supports SPRN_AMR update with MSR[PR] = 1
-     */
-    if (!early_cpu_has_feature(CPU_FTR_ARCH_206))
-        return 0;
-
    ret = of_scan_flat_dt(dt_scan_storage_keys, &pkeys_total);
    if (ret == 0) {
        /*

@@ -124,6 +118,12 @@ void __init pkey_early_init_devtree(void)
             __builtin_popcountl(ARCH_VM_PKEY_FLAGS >> VM_PKEY_SHIFT)
                != (sizeof(u64) * BITS_PER_BYTE));

+    /*
+     * Only P7 and above supports SPRN_AMR update with MSR[PR] = 1
+     */
+    if (!early_cpu_has_feature(CPU_FTR_ARCH_206))
+        return;
+
    /* scan the device tree for pkey feature */
    pkeys_total = scan_pkey_feature();
    if (!pkeys_total)