linux.git/arch/powerpc/kernel/paca.c, branch v4.12

powerpc/mm/hash: Store addr_limit in PACA

2017-04-01T10:12:27+00:00

We optmize the slice page size array copy to paca by copying only the
range based on addr_limit. This will require us to not look at page size
array beyond addr_limit in PACA on slb fault. To enable that copy task
size to paca which will be used during slb fault.

Signed-off-by: Aneesh Kumar K.V 
[mpe: Rename from task_size to addr_limit, consolidate #ifdefs]
Signed-off-by: Michael Ellerman

powerpc/mm: Add addr_limit to mm_context and use it to derive max slice index

2017-04-01T10:12:20+00:00

In the followup patch, we will increase the slice array size to handle
512TB range, but will limit the max addr to 128TB. Avoid doing
unnecessary computation and avoid doing slice mask related operation
above address limit.

Signed-off-by: Aneesh Kumar K.V 
Signed-off-by: Michael Ellerman

powerpc/mm: Move copy_mm_to_paca to paca.c

2017-03-31T12:09:54+00:00

We also update the function arg to struct mm_struct. Move this so that function
finds the definition of struct mm_struct. No functional change in this patch.

Signed-off-by: Aneesh Kumar K.V 
Signed-off-by: Michael Ellerman

sched/headers: Prepare to move 'init_task' and 'init_thread_union' from to

2017-03-02T07:42:38+00:00

Update all usage sites first.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

powerpc/mm: Convert early cpu/mmu feature check to use the new helpers

2016-08-01T01:15:01+00:00

This switches early feature checks to use the non static key variant of
the function. In later patches we will be switching cpu_has_feature()
and mmu_has_feature() to use static keys and we can use them only after
static key/jump label is initialized. Any check for feature before jump
label init should be done using this new helper.

Signed-off-by: Aneesh Kumar K.V 
Signed-off-by: Michael Ellerman

powerpc: Create a helper for getting the kernel toc value

2016-03-07T03:53:52+00:00

Move the logic to work out the kernel toc pointer into a header. This is
a good cleanup, and also means we can use it elsewhere in future.

Reviewed-by: Kamalesh Babulal 
Reviewed-by: Torsten Duwe 
Reviewed-by: Balbir Singh 
Signed-off-by: Michael Ellerman 
Tested-by: Kamalesh Babulal

powerpc/book3e-64: Don't limit paca to 256 MiB

2015-10-27T23:13:28+00:00

This limit only makes sense on book3s, and on book3e it can cause
problems with kdump if we don't have any memory under 256 MiB.

Signed-off-by: Scott Wood

powerpc/kernel: Avoid memory corruption at early stage

2015-01-23T03:02:52+00:00

When calling to early_setup(), we pick "boot_paca" up for the master CPU
and initialize that with initialise_paca(). At that point, the SLB
shadow buffer isn't populated yet. Updating the SLB shadow buffer should
corrupt what we had in physical address 0 where the trap instruction is
usually stored.

This hasn't been observed to cause any trouble in practice, but is
obviously fishy.

Fixes: 6f4441ef7009 ("powerpc: Dynamically allocate slb_shadow from memblock")
Signed-off-by: Gavin Shan 
Signed-off-by: Michael Ellerman

KVM: PPC: Book3S PR: Rework SLB switching code

2014-05-30T12:26:30+00:00

On LPAR guest systems Linux enables the shadow SLB to indicate to the
hypervisor a number of SLB entries that always have to be available.

Today we go through this shadow SLB and disable all ESID's valid bits.
However, pHyp doesn't like this approach very much and honors us with
fancy machine checks.

Fortunately the shadow SLB descriptor also has an entry that indicates
the number of valid entries following. During the lifetime of a guest
we can just swap that value to 0 and don't have to worry about the
SLB restoration magic.

While we're touching the code, let's also make it more readable (get
rid of rldicl), allow it to deal with a dynamic number of bolted
SLB entries and only do shadow SLB swizzling on LPAR systems.

Signed-off-by: Alexander Graf

powerpc/ppc64: Gracefully handle early interrupts

2014-04-07T00:33:15+00:00

If we take an interrupt such as a trap caused by a BUG_ON before the
MMU has been setup, the interrupt handlers try to enable virutal mode
and cause a recursive crash, making the original problem very hard
to debug.

This fixes it by adjusting the "kernel_msr" value in the PACA so that
it only has MSR_IR and MSR_DR (translation for instruction and data)
set after the MMU has been initialized for the processor.

We may still not have a console yet but at least we don't get into
a recursive fault (and early debug console or memory dump via JTAG
of the kernel buffer *will* give us the proper error).

Signed-off-by: Benjamin Herrenschmidt