1013862 Commits

Author SHA1 Message Date
Christophe Leroy
e72421a085 powerpc: Define swapper_pg_dir[] in C
Don't duplicate swapper_pg_dir[] in each platform's head.S

Define it in mm/pgtable.c

Define MAX_PTRS_PER_PGD because on book3s/64 PTRS_PER_PGD is
not a constant.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5e3f1b8a4695c33ccc80aa3870e016bef32b85e1.1623063174.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:10 +10:00
Christophe Leroy
45b30fafe5 powerpc: Define empty_zero_page[] in C
At the time being, empty_zero_page[] is defined in each
platform head.S.

Define it in mm/mem.c instead, and put it in BSS section instead
of the DATA section. Commit 5227cfa71f9e ("arm64: mm: place
empty_zero_page in bss") explains why it is interesting to have
it in BSS.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5838caffa269e0957c5a50cc85477876220298b0.1623063174.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:10 +10:00
Christophe Leroy
a1ea0ca8a6 powerpc/selftests: Use gettid() instead of getppid() for null_syscall
gettid() is 10% lighter than getppid(), use it for null_syscall selftest.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0ad62673d3e063f848e7c99d719bb966efd433e8.1622809833.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:10 +10:00
Christophe Leroy
e2c043163d powerpc/nohash: Remove DEBUG_HARDER
DEBUG_HARDER is not user selectable.

Remove it together with related messages.

Also remove two pr_devel() messages that should
likely have been pr_hard().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0f25109b0e12fdd1e6541dedbb2212cc53526a57.1622712515.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:10 +10:00
Christophe Leroy
a36c0faf3d powerpc/nohash: Remove DEBUG_CLAMP_LAST_CONTEXT
DEBUG_CLAMP_LAST_CONTEXT was there in the old days to reduce
number of contexts in order to ease debugging implementation
of context switching, but that's been quite stable during
years now.

As it is not user selectable, remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/da81837b452e8b9f1657b529b9c3050dc10b9770.1622712515.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:09 +10:00
Christophe Leroy
dac3db1edf powerpc/nohash: Remove DEBUG_MAP_CONSISTENCY
mmu_context handling has been there for years, so we
would know if there was problems with maps.

DEBUG_MAP_CONSISTENCY is not user selectable, remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/6fe2b88956db53f8d6ee221525b2c5dc6aec82c6.1622712515.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:09 +10:00
Christophe Leroy
c13066e53a powerpc/nohash: Remove CONFIG_SMP #ifdefery in mmu_context.h
Everything can be done even when CONFIG_SMP is not selected.

Just use IS_ENABLED() where relevant and rely on GCC to
opt out unneeded code and variables when CONFIG_SMP is not set.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/cc13b87b0f750a538621876ecc24c22a07e7c8be.1622712515.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:09 +10:00
Christophe Leroy
a56ab7c729 powerpc/nohash: Convert set_context() to C
ppc8xx already has set_context() in C.

Other ones have it in assembly. The only thing it does is to
write the context id into SPRN_PID.

Do it in C.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a5d0759064f3831c6b88af49ef5d3b05ba1c4dad.1622712515.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:09 +10:00
Christophe Leroy
25910260ff powerpc/nohash: Refactor update of BDI2000 pointers in switch_mmu_context()
Instead of duplicating the update of BDI2000 pointers in
set_context(), do it directly from switch_mmu_context().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4c54997edd3548fa54717915e7c6ebaf60f208c0.1622712515.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:09 +10:00
Christophe Leroy
240efd717c powerpc/kuap: Force inlining of all first level KUAP helpers.
All KUAP helpers defined in asm/kup.h are single line functions
that should be inlined. But on book3s/32 build, we get many
instances of <prevent_write_to_user.constprop.0>.

Force inlining of those helpers.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8479a862e165a57a855292d47e24c259a578f5a0.1622711627.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:09 +10:00
Christophe Leroy
cb2f1fb205 powerpc/kuap: Remove to/from/size parameters of prevent_user_access()
prevent_user_access() doesn't use anymore to/from/size parameters.

Remove them.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b7113662fd2c26e4c33e9d705de324bd3860822e.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:09 +10:00
Christophe Leroy
d008f8f8a0 powerpc/kuap: Remove KUAP_CURRENT_XXX
book3s/32 was the only user of KUAP_CURRENT_XXX.

After rework of book3s/32 KUAP, it is not used anymore.

Remove them.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/549214ecf6887d965645e664520d4886663c5ffb.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:09 +10:00
Christophe Leroy
9f5bd8f147 powerpc/32s: Activate KUAP and KUEP by default
Now that KUAP and KUEP have been significantly optimised and can be
disabled at boot time using 'nosmap' and 'nosmep' kernel parameters,
them can be active by default like in other powerpc platforms.

It is still possible to disable them completely in the configuration.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/86c7c74a3ba5312daea7e9658b096e2bcc6f4b64.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:08 +10:00
Christophe Leroy
16132529ce powerpc/32s: Rework Kernel Userspace Access Protection
On book3s/32, KUAP is provided by toggling Ks bit in segment registers.
One segment register addresses 256M of virtual memory.

At the time being, KUAP implements a complex logic to apply the
unlock/lock on the exact number of segments covering the user range
to access, with saving the boundaries of the range of segments in
a member of thread struct.

But most if not all user accesses are within a single segment.

Rework KUAP with a different approach:
- Open only one segment, the one corresponding to the starting
address of the range to be accessed.
- If a second segment is involved, it will generate a page fault. The
segment will then be open by the page fault handler.

The kuap member of thread struct will now contain:
- The start address of the current on going user access, that will be
used to know which segment to lock at the end of the user access.
- ~0 when no user access is open
- ~1 when additionnal segments are opened by a page fault.

Then, at lock time
- When only one segment is open, close it.
- When several segments are open, close all user segments.

Almost 100% of the time, only one segment will be involved.

In interrupts, inline the function that unlock/lock all segments,
because not inlining them implies a lot of register save/restore.

With the patch, writing value 128 in userspace in perf_copy_attr() is
done with 16 instructions:

    3890:	93 82 04 dc 	stw     r28,1244(r2)
    3894:	7d 20 e5 26 	mfsrin  r9,r28
    3898:	55 29 00 80 	rlwinm  r9,r9,0,2,0
    389c:	7d 20 e1 e4 	mtsrin  r9,r28
    38a0:	4c 00 01 2c 	isync

    38a4:	39 20 00 80 	li      r9,128
    38a8:	91 3c 00 00 	stw     r9,0(r28)

    38ac:	81 42 04 dc 	lwz     r10,1244(r2)
    38b0:	39 00 ff ff 	li      r8,-1
    38b4:	91 02 04 dc 	stw     r8,1244(r2)
    38b8:	2c 0a ff fe 	cmpwi   r10,-2
    38bc:	41 82 00 88 	beq     3944 <perf_copy_attr+0x36c>
    38c0:	7d 20 55 26 	mfsrin  r9,r10
    38c4:	65 29 40 00 	oris    r9,r9,16384
    38c8:	7d 20 51 e4 	mtsrin  r9,r10
    38cc:	4c 00 01 2c 	isync
...
    3944:	48 00 00 01 	bl      3944 <perf_copy_attr+0x36c>
			3944: R_PPC_REL24	kuap_lock_all_ool

Before the patch it was 118 instructions. In reality only 42 are
executed in most cases, but GCC is not able to see that a properly
aligned user access cannot involve more than one segment.

    5060:	39 1d 00 04 	addi    r8,r29,4
    5064:	3d 20 b0 00 	lis     r9,-20480
    5068:	7c 08 48 40 	cmplw   r8,r9
    506c:	40 81 00 08 	ble     5074 <perf_copy_attr+0x2cc>
    5070:	3d 00 b0 00 	lis     r8,-20480
    5074:	39 28 ff ff 	addi    r9,r8,-1
    5078:	57 aa 00 06 	rlwinm  r10,r29,0,0,3
    507c:	55 29 27 3e 	rlwinm  r9,r9,4,28,31
    5080:	39 29 00 01 	addi    r9,r9,1
    5084:	7d 29 53 78 	or      r9,r9,r10
    5088:	91 22 04 dc 	stw     r9,1244(r2)
    508c:	7d 20 ed 26 	mfsrin  r9,r29
    5090:	55 29 00 80 	rlwinm  r9,r9,0,2,0
    5094:	7c 08 50 40 	cmplw   r8,r10
    5098:	40 81 00 c0 	ble     5158 <perf_copy_attr+0x3b0>
    509c:	7d 46 50 f8 	not     r6,r10
    50a0:	7c c6 42 14 	add     r6,r6,r8
    50a4:	54 c6 27 be 	rlwinm  r6,r6,4,30,31
    50a8:	7d 20 51 e4 	mtsrin  r9,r10
    50ac:	3c ea 10 00 	addis   r7,r10,4096
    50b0:	39 29 01 11 	addi    r9,r9,273
    50b4:	7f 88 38 40 	cmplw   cr7,r8,r7
    50b8:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    50bc:	40 9d 00 9c 	ble     cr7,5158 <perf_copy_attr+0x3b0>

    50c0:	2f 86 00 00 	cmpwi   cr7,r6,0
    50c4:	41 9e 00 4c 	beq     cr7,5110 <perf_copy_attr+0x368>
    50c8:	2f 86 00 01 	cmpwi   cr7,r6,1
    50cc:	41 9e 00 2c 	beq     cr7,50f8 <perf_copy_attr+0x350>
    50d0:	2f 86 00 02 	cmpwi   cr7,r6,2
    50d4:	41 9e 00 14 	beq     cr7,50e8 <perf_copy_attr+0x340>
    50d8:	7d 20 39 e4 	mtsrin  r9,r7
    50dc:	39 29 01 11 	addi    r9,r9,273
    50e0:	3c e7 10 00 	addis   r7,r7,4096
    50e4:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    50e8:	7d 20 39 e4 	mtsrin  r9,r7
    50ec:	39 29 01 11 	addi    r9,r9,273
    50f0:	3c e7 10 00 	addis   r7,r7,4096
    50f4:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    50f8:	7d 20 39 e4 	mtsrin  r9,r7
    50fc:	3c e7 10 00 	addis   r7,r7,4096
    5100:	39 29 01 11 	addi    r9,r9,273
    5104:	7f 88 38 40 	cmplw   cr7,r8,r7
    5108:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    510c:	40 9d 00 4c 	ble     cr7,5158 <perf_copy_attr+0x3b0>
    5110:	7d 20 39 e4 	mtsrin  r9,r7
    5114:	39 29 01 11 	addi    r9,r9,273
    5118:	3c c7 10 00 	addis   r6,r7,4096
    511c:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    5120:	7d 20 31 e4 	mtsrin  r9,r6
    5124:	39 29 01 11 	addi    r9,r9,273
    5128:	3c c6 10 00 	addis   r6,r6,4096
    512c:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    5130:	7d 20 31 e4 	mtsrin  r9,r6
    5134:	39 29 01 11 	addi    r9,r9,273
    5138:	3c c7 30 00 	addis   r6,r7,12288
    513c:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    5140:	7d 20 31 e4 	mtsrin  r9,r6
    5144:	3c e7 40 00 	addis   r7,r7,16384
    5148:	39 29 01 11 	addi    r9,r9,273
    514c:	7f 88 38 40 	cmplw   cr7,r8,r7
    5150:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    5154:	41 9d ff bc 	bgt     cr7,5110 <perf_copy_attr+0x368>

    5158:	4c 00 01 2c 	isync
    515c:	39 20 00 80 	li      r9,128
    5160:	91 3d 00 00 	stw     r9,0(r29)

    5164:	38 e0 00 00 	li      r7,0
    5168:	90 e2 04 dc 	stw     r7,1244(r2)
    516c:	7d 20 ed 26 	mfsrin  r9,r29
    5170:	65 29 40 00 	oris    r9,r9,16384
    5174:	40 81 00 c0 	ble     5234 <perf_copy_attr+0x48c>
    5178:	7d 47 50 f8 	not     r7,r10
    517c:	7c e7 42 14 	add     r7,r7,r8
    5180:	54 e7 27 be 	rlwinm  r7,r7,4,30,31
    5184:	7d 20 51 e4 	mtsrin  r9,r10
    5188:	3d 4a 10 00 	addis   r10,r10,4096
    518c:	39 29 01 11 	addi    r9,r9,273
    5190:	7c 08 50 40 	cmplw   r8,r10
    5194:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    5198:	40 81 00 9c 	ble     5234 <perf_copy_attr+0x48c>

    519c:	2c 07 00 00 	cmpwi   r7,0
    51a0:	41 82 00 4c 	beq     51ec <perf_copy_attr+0x444>
    51a4:	2c 07 00 01 	cmpwi   r7,1
    51a8:	41 82 00 2c 	beq     51d4 <perf_copy_attr+0x42c>
    51ac:	2c 07 00 02 	cmpwi   r7,2
    51b0:	41 82 00 14 	beq     51c4 <perf_copy_attr+0x41c>
    51b4:	7d 20 51 e4 	mtsrin  r9,r10
    51b8:	39 29 01 11 	addi    r9,r9,273
    51bc:	3d 4a 10 00 	addis   r10,r10,4096
    51c0:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    51c4:	7d 20 51 e4 	mtsrin  r9,r10
    51c8:	39 29 01 11 	addi    r9,r9,273
    51cc:	3d 4a 10 00 	addis   r10,r10,4096
    51d0:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    51d4:	7d 20 51 e4 	mtsrin  r9,r10
    51d8:	3d 4a 10 00 	addis   r10,r10,4096
    51dc:	39 29 01 11 	addi    r9,r9,273
    51e0:	7c 08 50 40 	cmplw   r8,r10
    51e4:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    51e8:	40 81 00 4c 	ble     5234 <perf_copy_attr+0x48c>
    51ec:	7d 20 51 e4 	mtsrin  r9,r10
    51f0:	39 29 01 11 	addi    r9,r9,273
    51f4:	3c ea 10 00 	addis   r7,r10,4096
    51f8:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    51fc:	7d 20 39 e4 	mtsrin  r9,r7
    5200:	39 29 01 11 	addi    r9,r9,273
    5204:	3c e7 10 00 	addis   r7,r7,4096
    5208:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    520c:	7d 20 39 e4 	mtsrin  r9,r7
    5210:	39 29 01 11 	addi    r9,r9,273
    5214:	3c ea 30 00 	addis   r7,r10,12288
    5218:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    521c:	7d 20 39 e4 	mtsrin  r9,r7
    5220:	3d 4a 40 00 	addis   r10,r10,16384
    5224:	39 29 01 11 	addi    r9,r9,273
    5228:	7c 08 50 40 	cmplw   r8,r10
    522c:	55 29 02 06 	rlwinm  r9,r9,0,8,3
    5230:	41 81 ff bc 	bgt     51ec <perf_copy_attr+0x444>

    5234:	4c 00 01 2c 	isync

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Export the ool handlers to fix build errors]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d9121f96a7c4302946839a0771f5d1daeeb6968c.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:08 +10:00
Christophe Leroy
6b4d630068 powerpc/32s: Allow disabling KUAP at boot time
PPC64 uses MMU features to enable/disable KUAP at boot time.
But feature fixups are applied way too early on PPC32.

Now that all KUAP related actions are in C following the
conversion of KUAP initial setup and context switch in C,
static branches can be used to enable/disable KUAP.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Export disable_kuap_key to fix build errors]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/cd79e8008455fba5395d099f9bb1305c039b931c.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:08 +10:00
Christophe Leroy
50d2f104cd powerpc/32s: Allow disabling KUEP at boot time
PPC64 uses MMU features to enable/disable KUEP at boot time.
But feature fixups are applied way too early on PPC32.

Now that all KUEP related actions are in C following the
conversion of KUEP initial setup and context switch in C,
static branches can be used to enable/disable KUEP.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7745a2c3a08ec46302920a3f48d1cb9b5469dbbb.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:08 +10:00
Christophe Leroy
86f46f3432 powerpc/32s: Initialise KUAP and KUEP in C
In order to selectively activate KUAP and KUEP in a following patch,
perform KUAP and KUEP initialisation in C.

Unlike PPC64, PPC32 doesn't have an early_setup_secondary(),
so do it in start_secondary().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/87be72023448dd4e476744ed279b8c04b8d08a1c.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:08 +10:00
Christophe Leroy
882136fb2f powerpc/32s: Simplify calculation of segment register content
segment register has VSID on bits 8-31.
Bits 4-7 are reserved, there is no requirement to set them to 0.

VSIDs are calculated from VSID of SR0 by adding 0x111.

Even with highest possible VSID which would be 0xFFFFF0,
adding 16 times 0x111 results in 0x1001100.

So, the reserved bits are never overflowed, no need to clear
the reserved bits after each calculation.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ddc1cfd2ec8f3b2395c6a4d7f2b0c1aa1b1e64fb.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:08 +10:00
Christophe Leroy
863771a28e powerpc/32s: Convert switch_mmu_context() to C
switch_mmu_context() does things that can easily be done in C.

For updating user segments, we have update_user_segments().

As mentionned in commit b5efec00b671 ("powerpc/32s: Move KUEP
locking/unlocking in C"), update_user_segments() has the loop
unrolled which is a significant performance gain.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/05c0875ad8220c03452c3a334946e207c6ca04d6.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:08 +10:00
Christophe Leroy
7235bb3593 powerpc/32s: move CTX_TO_VSID() into mmu-hash.h
In order to reuse it in switch_mmu_context(), this
patch moves CTX_TO_VSID() macro into asm/book3s/32/mmu-hash.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/26b36ef2939234a04b37baf6ffe50cba81f5d1b7.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:08 +10:00
Christophe Leroy
91bb30822a powerpc/32s: Refactor update of user segment registers
KUEP implements the update of user segment registers.

Move it into mmu-hash.h in order to use it from other places.

And inline kuep_lock() and kuep_unlock(). Inlining kuep_lock() is
important for system_call_exception(), otherwise system_call_exception()
has to save into stack the system call parameters that are used just
after, and doing that takes more instructions than kuep_lock() itself.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/24591ca480d14a62ef910e38a5273d551262c4a2.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:07 +10:00
Christophe Leroy
91ec66719d powerpc/32s: Move setup_{kuep/kuap}() into {kuep/kuap}.c
Avoids the #ifdef in mmu.c

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0b7a13d414837e58264edc336b89c2fe9f35f9bc.1622708530.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:07 +10:00
Christophe Leroy
f6025a140b powerpc/8xx: Allow disabling KUAP at boot time
PPC64 uses MMU features to enable/disable KUAP at boot time.
But feature fixups are applied way too early on PPC32.

But since commit c16728835eec ("powerpc/32: Manage KUAP in C"),
all KUAP is in C so it is now possible to use static branches.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3dca510ce555335261a47c4799167da698f569c0.1622782111.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:07 +10:00
Christophe Leroy
10248dcba1 powerpc/44x: Implement Kernel Userspace Exec Protection (KUEP)
Powerpc 44x has two bits for exec protection in TLBs: one
for user (UX) and one for superviser (SX).

Clear SX on user pages in TLB miss handlers to provide KUEP.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/169310e08152aa1d96c979770291d165ec6896ae.1622616032.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:07 +10:00
Christophe Leroy
c0ca0fe08c powerpc: Remove CONFIG_PPC_MMU_NOHASH_32
Since commit Fixes: 555904d07eef ("powerpc/8xx: MM_SLICE is not needed anymore"),
CONFIG_PPC_MMU_NOHASH_32 has not been used.

Remove it.

Reported-by: Tom Rix <trix@redhat.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/bf1e074f6fb213a1c4cc4964370bdce4b648d647.1622706812.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:07 +10:00
Christophe Leroy
0e628ad2d6 powerpc/optprobes: use PPC_RAW_ macros
Use PPC_RAW_ macros to simplify the code.

And use PPC_LO/PPC_HI instead of IMM_L/IMM_H which are for
internal use inside ppc-opcode.h

Those macros are self explanatory, comments can go as well.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5a167b8ba4d33a5c09cd504f0c862e25ffe85459.1621516826.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:07 +10:00
Christophe Leroy
f38adf86ce powerpc/optprobes: Compact code source a bit.
Now that lines can be up to 100 chars long, minimise the
amount of split lines to increase readability.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8ebbd977ea8cf8d706d82458f2a21acd44562a99.1621516826.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:07 +10:00
Christophe Leroy
afd3287c88 powerpc/optprobes: Minimise casts
nip is already an unsigned long, no cast needed.

op_callback_addr and emulate_step_addr are kprobe_opcode_t *.
There value is obtained with ppc_kallsyms_lookup_name() which
returns 'unsigned long', and there values are used create_branch()
which expects 'unsigned long'. So change them to 'unsigned long'
to avoid casting them back and forth.

can_optimize() used p->addr several times as 'unsigned long'.
Use a local 'unsigned long' variable and avoid casting multiple times.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e03192a6d4123242a275e71ce2ba0bb4d90700c1.1621516826.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:06 +10:00
Christophe Leroy
077c4dedef powerpc/inst: Refactor PPC32 and PPC64 versions
ppc_inst() ppc_inst_prefixed() ppc_inst_swab() can easily be made common
to both PPC32 and PPC64.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d54c63dcac6d190e1cc0d2fe3259d6e621928cdf.1621516826.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:06 +10:00
Christophe Leroy
69d4d6e5fd powerpc: Don't use 'struct ppc_inst' to reference instruction location
'struct ppc_inst' is an internal representation of an instruction, but
in-memory instructions are and will remain a table of 'u32' forever.

Replace all 'struct ppc_inst *' used for locating an instruction in
memory by 'u32 *'. This removes a lot of undue casts to 'struct
ppc_inst *'.

It also helps locating ab-use of 'struct ppc_inst' dereference.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Fix ppc_inst_next(), use u32 instead of unsigned int]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7062722b087228e42cbd896e39bfdf526d6a340a.1621516826.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:00 +10:00
Christophe Leroy
e90a21ea80 powerpc/lib/code-patching: Don't use struct 'ppc_inst' for runnable code in tests.
'struct ppc_inst' is meant to represent an instruction internally, it
is not meant to dereference code in memory.

For testing code patching, use patch_instruction() to properly
write into memory the code to be tested.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d8425fb42a4adebc35b7509f121817eeb02fac31.1621516826.git.christophe.leroy@csgroup.eu
2021-06-17 00:07:51 +10:00
Christophe Leroy
6c0d181daa powerpc/lib/code-patching: Make instr_is_branch_to_addr() static
instr_is_branch_to_addr() is only used in code-patching.c

Make it static.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5f6b9c8c83170ed310953eac2f5b14539bfc964a.1621516826.git.christophe.leroy@csgroup.eu
2021-06-16 23:35:57 +10:00
Christophe Leroy
18c85964b1 powerpc: Do not dereference code as 'struct ppc_inst' (uprobe, code-patching, feature-fixups)
'struct ppc_inst' is an internal structure to represent an instruction,
it is not directly the representation of that instruction in text code.
It is not meant to map and dereference code.

Dereferencing code directly through 'struct ppc_inst' has two main issues:
- On powerpc, structs are expected to be 8 bytes aligned while code is
spread every 4 byte.
- Should a non prefixed instruction lie at the end of the page and the
following page not be mapped, it would generate a page fault.

In-memory code must be accessed with ppc_inst_read().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c9a1201dd0a66b4a0f91f0fb46d9385cbf030feb.1621516826.git.christophe.leroy@csgroup.eu
2021-06-16 23:35:57 +10:00
Christophe Leroy
036b5560be powerpc/inst: Avoid pointer dereferencing in ppc_inst_equal()
Avoid casting/dereferencing ppc_inst() as u64* , check each member
of the struct when relevant.

And remove the 0xff initialisation of the suffix for non
prefixed instruction. An instruction with 0xff as a suffix
might be invalid, but still is a prefixed instruction and
has to be considered as this.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d8b155e930b7a9708ca110e8ff0ace6713a7af75.1621516826.git.christophe.leroy@csgroup.eu
2021-06-16 23:35:57 +10:00
Christophe Leroy
042e0860e1 powerpc/inst: Improve readability of get_user_instr() and friends
Remove unneeded line splits.

And remove unneeded local variable initialisation.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fb097fda78cc6852905ef00f8f7bf371b6cc66f7.1621516826.git.christophe.leroy@csgroup.eu
2021-06-16 23:35:30 +10:00
Christophe Leroy
9134806e14 powerpc/inst: Reduce casts in get_user_instr()
Declare __gui_ptr as 'u32 *' instead of casting it at each use to
'unsigned int *' (which is an equivalent type).

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Use u32 * instead of unsigned int *]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2c2123998e05535d08ba03a96ea1eea921d06a86.1621516826.git.christophe.leroy@csgroup.eu
2021-06-16 23:35:10 +10:00
Christophe Leroy
b3a9e52323 powerpc/inst: Fix sparse detection on get_user_instr()
get_user_instr() lacks sparse detection for the __user tag.

This is because __gui_ptr is assigned with a cast.

Fix that by adding a __chk_user_ptr()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0320e5b41a794fd456ab8c5993bbfadcf9e1d8b4.1621516826.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:49 +10:00
Christophe Leroy
f30becb5e9 powerpc: Replace PPC_INST_NOP by PPC_RAW_NOP()
On the road to removing all PPC_INST_xx defines in
asm/ppc-opcodes.h, change PPC_INST_NOP to PPC_RAW_NOP().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ad46c195ca1b8572629ef07ba6bfe247585239a6.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:49 +10:00
Christophe Leroy
deefd0ae99 powerpc/traps: Start using PPC_RAW_xx() macros
Start using PPC_RAW_xx() macros where relevant.

PPC_INST_SYNC is used to both represent the 'sync' instruction and
the family of synchronisation instructions. Keep it for the later,
maybe we'll change the name in the future to avoid confusion.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0945c155d6cb113431185fc1296ac127359fe29b.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:48 +10:00
Christophe Leroy
ef909ba954 powerpc/lib/feature-fixups: Use PPC_RAW_xxx() macros
Use PPC_RAW_xxx() macros instead of open coding assembly
opcodes.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Fix bad converison in do_stf_exit_barrier_fixups()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e79cd8e111ca13bf8c61a384bac365aa7e207647.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:48 +10:00
Christophe Leroy
e0ea08c0ca powerpc/ebpf32: Use _Rx macros instead of __REG_Rx ones
To increase readability, use _Rx macros instead of __REG_Rx.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/eb7ec6297b5d16f141c5866da3975b418e47431b.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:48 +10:00
Christophe Leroy
e08021f8db powerpc/ebpf64: Use PPC_RAW_MFLR()
Use PPC_RAW_MFLR() instead of open coding with PPC_INST_MFLR.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c1887623e91e8b4da36e669e4c74de86320a5092.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:48 +10:00
Christophe Leroy
5a03e1e972 powerpc/ftrace: Use PPC_RAW_MFLR() and PPC_RAW_NOP()
Use PPC_RAW_MFLR() instead of open coding with PPC_INST_MFLR.

Same for PPC_INST_NOP.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/98fd4d717810b7c4032a1edf62dd6fe638e64329.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:48 +10:00
Christophe Leroy
e730459756 powerpc/security: Use PPC_RAW_BLR() and PPC_RAW_NOP()
On the road to remove all use of PPC_INST_xxx, replace
PPC_INST_BLR by PPC_RAW_BLR(). Same for PPC_INST_NOP.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c04f88d0e53d2122fbbe92226892a01ebc668b6a.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:48 +10:00
Christophe Leroy
47b04699d0 powerpc/modules: Use PPC_RAW_xx() macros
To improve readability, use PPC_RAW_xx() macros instead of
open coding. Those macros are self-explanatory so the comments
can go as well.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/99d9ee8849d3992beeadb310a665aae01c3abfb1.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:48 +10:00
Christophe Leroy
1c9debbc2e powerpc/signal: Use PPC_RAW_xx() macros
To improve readability, use PPC_RAW_xx() macros instead of
open coding. Those macros are self-explanatory so the comments
can go as well.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4ca2bfdca2f47a293d05f61eb3c4e487ee170f1f.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:47 +10:00
Christophe Leroy
8804d5beef powerpc/lib/code-patching: Use PPC_RAW_() macros
Instead of open coding with PPC_INST_ defines, use
PPC_RAW_() macros. It improves readability.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8c92f1d9e825ee47c6f88fe43ad42d2a8cc2ab4a.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:47 +10:00
Christophe Leroy
07cd18320e powerpc/opcodes: Add shorter macros for registers for use with PPC_RAW_xx()
Today we have __REG_Rx macros . They are mainly meant for
internal use by macros __PPC_RA() and friends macros which
allows uses like __PPC_RA(R12).

When used with PPC_RAW_xx() macros, it gives a result which is
not very readable.

Add shorter macros _Rx in order to improve readability when
used with PPC_RAW_xx() macros.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ec34d92b7c2f810622261acfeeed4b0a0f4d01bd.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:47 +10:00
Christophe Leroy
148a047602 powerpc: Rework PPC_RAW_xxx() macros for prefixed instructions
At the time being, we have PPC_RAW_PLXVP() and PPC_RAW_PSTXVP() which
provide a 64 bits value, and then it gets split by open coding to
format it into a 'struct ppc_inst' instruction.

Instead, define a PPC_RAW_xxx_P() and a PPC_RAW_xxx_S() to be used
as is.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5d146b31b943e7ad674894421db4feef54804b9b.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:47 +10:00
Christophe Leroy
359c2ca74d powerpc: Don't handle ALTIVEC/SPE in ASM in _switch(). Do it in C.
_switch() saves and restores ALTIVEC and SPE status.
For altivec this is redundant with what __switch_to() does with
save_sprs() and restore_sprs() and giveup_all() before
calling _switch().

Add support for SPI in save_sprs() and restore_sprs() and
remove things from _switch().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8ab21fd93d6e0047aa71e6509e5e312f14b2991b.1620998075.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:47 +10:00