Pull powerpc updates from Michael Ellerman:
- Convert pseries & powernv to use MSI IRQ domains.
- Rework the pseries CPU numbering so that CPUs that are removed, and
later re-added, are given a CPU number on the same node as
previously, when possible.
- Add support for a new more flexible device-tree format for specifying
NUMA distances.
- Convert powerpc to GENERIC_PTDUMP.
- Retire sbc8548 and sbc8641d board support.
- Various other small features and fixes.
Thanks to Alexey Kardashevskiy, Aneesh Kumar K.V, Anton Blanchard,
Cédric Le Goater, Christophe Leroy, Emmanuel Gil Peyrot, Fabiano Rosas,
Fangrui Song, Finn Thain, Gautham R. Shenoy, Hari Bathini, Joel
Stanley, Jordan Niethe, Kajol Jain, Laurent Dufour, Leonardo Bras, Lukas
Bulwahn, Marc Zyngier, Masahiro Yamada, Michal Suchanek, Nathan
Chancellor, Nicholas Piggin, Parth Shah, Paul Gortmaker, Pratik R.
Sampat, Randy Dunlap, Sebastian Andrzej Siewior, Srikar Dronamraju, Wan
Jiabing, Xiongwei Song, and Zheng Yongjun.
* tag 'powerpc-5.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (154 commits)
powerpc/bug: Cast to unsigned long before passing to inline asm
powerpc/ptdump: Fix generic ptdump for 64-bit
KVM: PPC: Fix clearing never mapped TCEs in realmode
powerpc/pseries/iommu: Rename "direct window" to "dma window"
powerpc/pseries/iommu: Make use of DDW for indirect mapping
powerpc/pseries/iommu: Find existing DDW with given property name
powerpc/pseries/iommu: Update remove_dma_window() to accept property name
powerpc/pseries/iommu: Reorganize iommu_table_setparms*() with new helper
powerpc/pseries/iommu: Add ddw_property_create() and refactor enable_ddw()
powerpc/pseries/iommu: Allow DDW windows starting at 0x00
powerpc/pseries/iommu: Add ddw_list_new_entry() helper
powerpc/pseries/iommu: Add iommu_pseries_alloc_table() helper
powerpc/kernel/iommu: Add new iommu_table_in_use() helper
powerpc/pseries/iommu: Replace hard-coded page shift
powerpc/numa: Update cpu_cpu_map on CPU online/offline
powerpc/numa: Print debug statements only when required
powerpc/numa: convert printk to pr_xxx
powerpc/numa: Drop dbg in favour of pr_debug
powerpc/smp: Enable CACHE domain for shared processor
powerpc/smp: Update cpu_core_map on all PowerPc systems
...
Merge our fixes branch into next.
That lets us resolve a conflict in arch/powerpc/sysdev/xive/common.c.
Between cbc06f051c ("powerpc/xive: Do not skip CPU-less nodes when
creating the IPIs"), which moved request_irq() out of xive_init_ipis(),
and 17df41fec5 ("powerpc: use IRQF_NO_DEBUG for IPIs") which added
IRQF_NO_DEBUG to that request_irq() call, which has now moved.
In commit 1e688dd2a3 ("powerpc/bug: Provide better flexibility to
WARN_ON/__WARN_FLAGS() with asm goto") we changed WARN_ON(). Previously
it would take the warning condition, x, and double negate it before
converting the result to int, and passing that int to the underlying
inline asm. ie:
#define WARN_ON(x) ({
int __ret_warn_on = !!(x);
if (__builtin_constant_p(__ret_warn_on)) {
...
} else {
BUG_ENTRY(PPC_TLNEI " %4, 0",
BUGFLAG_WARNING | BUGFLAG_TAINT(TAINT_WARN),
"r" (__ret_warn_on));
The asm then does a full register width comparison with zero and traps
if it is non-zero (PPC_TLNEI).
The new code instead passes the full expression, x, with some arbitrary
type, to the inline asm:
#define WARN_ON(x) ({
...
do {
if (__builtin_constant_p((x))) {
...
} else {
...
WARN_ENTRY(PPC_TLNEI " %4, 0",
BUGFLAG_WARNING | BUGFLAG_TAINT(TAINT_WARN),
__label_warn_on, "r" (x));
As reported[1] by Nathan, when building with clang this can cause
spurious warnings to fire repeatedly at boot:
WARNING: CPU: 0 PID: 1 at lib/klist.c:62 .klist_add_tail+0x3c/0x110
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 5.14.0-rc7-next-20210825 #1
NIP: c0000000007ff81c LR: c00000000090a038 CTR: 0000000000000000
REGS: c0000000073c32a0 TRAP: 0700 Tainted: G W (5.14.0-rc7-next-20210825)
MSR: 8000000002029032 <SF,VEC,EE,ME,IR,DR,RI> CR: 22000a40 XER: 00000000
CFAR: c00000000090a034 IRQMASK: 0
GPR00: c00000000090a038 c0000000073c3540 c000000001be3200 0000000000000001
GPR04: c0000000072d65c0 0000000000000000 c0000000091ba798 c0000000091bb0a0
GPR08: 0000000000000001 0000000000000000 c000000008581918 fffffffffffffc00
GPR12: 0000000044000240 c000000001dd0000 c000000000012300 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR24: 0000000000000000 c0000000017e3200 0000000000000000 c000000001a0e778
GPR28: c0000000072d65b0 c0000000072d65a8 c000000007de72c8 c0000000073c35d0
NIP .klist_add_tail+0x3c/0x110
LR .bus_add_driver+0x148/0x290
Call Trace:
0xc0000000073c35d0 (unreliable)
.bus_add_driver+0x148/0x290
.driver_register+0xb8/0x190
.__hid_register_driver+0x70/0xd0
.redragon_driver_init+0x34/0x58
.do_one_initcall+0x130/0x3b0
.do_initcall_level+0xd8/0x188
.do_initcalls+0x7c/0xdc
.kernel_init_freeable+0x178/0x21c
.kernel_init+0x34/0x220
.ret_from_kernel_thread+0x58/0x60
Instruction dump:
fba10078 7c7d1b78 38600001 fb810070 3b9d0008 fbc10080 7c9e2378 389d0018
fb9d0008 fb9d0010 90640000 fbdd0000 <0b1e0000> e87e0018 28230000 41820024
The instruction dump shows that we are trapping because r30 is not zero:
tdnei r30,0
Where r30 = c000000007de72c8
The WARN_ON() comes from:
static void knode_set_klist(struct klist_node *knode, struct klist *klist)
{
knode->n_klist = klist;
/* no knode deserves to start its life dead */
WARN_ON(knode_dead(knode));
^^^^^^^^^^^^^^^^^
Where:
#define KNODE_DEAD 1LU
static bool knode_dead(struct klist_node *knode)
{
return (unsigned long)knode->n_klist & KNODE_DEAD;
}
The full disassembly shows that clang has not generated any code to
apply the "& KNODE_DEAD" to the n_klist pointer, which is surprising.
Nathan filed an LLVM bug [2], in which Eli Friedman explained that clang
believes it is only passing a single bit to the asm (ie. a bool) and so
the mask of bit 0 with 1 can be omitted, and suggested that if we want
the full 64-bit value passed to the inline asm we should cast to a
64-bit type (or 32-bit on 32-bits).
In fact we already do that for BUG_ENTRY(), which was added to fix a
possibly similar bug in 2005 in commit 32818c2eb6 ("[PATCH] ppc64: Fix
issue with gcc 4.0 compiled kernels").
So cast the value we pass to the inline asm to long.
For GCC this appears to have no effect on code generation, other than
causing sign extension in some cases.
[1]: http://lore.kernel.org/r/YSa1O4fcX1nNKqN/@Ryzen-9-3900X.localdomain
[2]: https://bugs.llvm.org/show_bug.cgi?id=51634
Fixes: 1e688dd2a3 ("powerpc/bug: Provide better flexibility to WARN_ON/__WARN_FLAGS() with asm goto")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210901112522.1085134-1-mpe@ellerman.id.au
Having a function to check if the iommu table has any allocation helps
deciding if a tbl can be reset for using a new DMA window.
It should be enough to replace all instances of !bitmap_empty(tbl...).
iommu_table_in_use() skips reserved memory, so we don't need to worry about
releasing it before testing. This causes iommu_table_release_pages() to
become unnecessary, given it is only used to remove reserved memory for
testing.
Also, only allow storing reserved memory values in tbl if they are valid
in the table, so there is no need to check it in the new helper.
Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210817063929.38701-3-leobras.c@gmail.com
Some functions assume IOMMU page size can only be 4K (pageshift == 12).
Update them to accept any page size passed, so we can use 64K pages.
In the process, some defines like TCE_SHIFT were made obsolete, and then
removed.
IODA3 Revision 3.0_prd1 (OpenPowerFoundation), Figures 3.4 and 3.5 show
a RPN of 52-bit, and considers a 12-bit pageshift, so there should be
no need of using TCE_RPN_MASK, which masks out any bit after 40 in rpn.
It's usage removed from tce_build_pSeries(), tce_build_pSeriesLP(), and
tce_buildmulti_pSeriesLP().
Most places had a tbl struct, so using tbl->it_page_shift was simple.
tce_free_pSeriesLP() was a special case, since callers not always have a
tbl struct, so adding a tceshift parameter seems the right thing to do.
Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210817063929.38701-2-leobras.c@gmail.com
Create an anonymous union for dsisr and esr regsiters, we can reference
esr to get the exception detail when CONFIG_4xx=y or CONFIG_BOOKE=y.
Otherwise, reference dsisr. This makes code more clear.
Signed-off-by: Xiongwei Song <sxwjean@gmail.com>
[mpe: Reword commit title]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210807010239.416055-2-sxwjean@me.com
After the L1 saves its PMU SPRs but before loading the L2's PMU SPRs,
switch the pmcregs_in_use field in the L1 lppaca to the value advertised
by the L2 in its VPA. On the way out of the L2, set it back after saving
the L2 PMU registers (if they were in-use).
This transfers the PMU liveness indication between the L1 and L2 at the
points where the registers are not live.
This fixes the nested HV bug for which a workaround was added to the L0
HV by commit 63279eeb7f ("KVM: PPC: Book3S HV: Always save guest pmu
for guest capable of nesting"), which explains the problem in detail.
That workaround is no longer required for guests that include this bug
fix.
Fixes: 360cae3137 ("KVM: PPC: Book3S HV: Nested guest entry via hypercall")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Link: https://lore.kernel.org/r/20210811160134.904987-10-npiggin@gmail.com
When the L0 runs a nested L2, there are several permutations of HFSCR
that can be relevant. The HFSCR that the L1 vcpu L1 requested, the
HFSCR that the L1 vcpu may use, and the HFSCR that is actually being
used to run the L2.
The L1 requested HFSCR is not accessible outside the nested hcall
handler, so copy that into a new kvm_nested_guest.hfscr field.
The permitted HFSCR is taken from the HFSCR that the L1 runs with,
which is also not accessible while the hcall is being made. Move
this into a new kvm_vcpu_arch.hfscr_permitted field.
These will be used by the next patch to improve facility handling
for nested guests, and later by facility demand faulting patches.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-7-npiggin@gmail.com
Have the TM softpatch emulation code set up the HFAC interrupt and
return -1 in case an instruction was executed with HFSCR bits clear,
and have the interrupt exit handler fall through to the HFAC handler.
When the L0 is running a nested guest, this ensures the HFAC interrupt
is correctly passed up to the L1.
The "direct guest" exit handler will turn these into PROGILL program
interrupts so functionality in practice will be unchanged. But it's
possible an L1 would want to handle these in a different way.
Also rearrange the FAC interrupt emulation code to match the HFAC format
while here (mainly, adding the FSCR_INTR_CAUSE mask).
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210811160134.904987-5-npiggin@gmail.com
Today we have:
#ifdef __powerpc64__
#define user_mode(regs) ((((regs)->msr) >> MSR_PR_LG) & 0x1)
#else
#define user_mode(regs) (((regs)->msr & MSR_PR) != 0)
#endif
With ppc64_defconfig, we get:
if (!user_mode(regs))
14b4: e9 3e 01 08 ld r9,264(r30)
14b8: 71 29 40 00 andi. r9,r9,16384
14bc: 41 82 07 a4 beq 1c60 <.emulate_instruction+0x7d0>
If taking the ppc32 definition of user_mode(), the exact same code
is generated for ppc64_defconfig.
So, only keep one version of user_mode(), preferably the one not
using MSR_PR_LG which should be kept internal to reg.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/000a28c51808bbd802b505af42d2cb316c2be7d3.1629216000.git.christophe.leroy@csgroup.eu
Commit b5efec00b6 ("powerpc/32s: Move KUEP locking/unlocking in C")
removed the 'isync' instruction after adding/removing NX bit in user
segments. The reasoning behind this change was that when setting the
NX bit we don't mind it taking effect with delay as the kernel never
executes text from userspace, and when clearing the NX bit this is
to return to userspace and then the 'rfi' should synchronise the
context.
However, it looks like on book3s/32 having a hash page table, at least
on the G3 processor, we get an unexpected fault from userspace, then
this is followed by something wrong in the verification of MSR_PR
at end of another interrupt.
This is fixed by adding back the removed isync() following update
of NX bit in user segment registers. Only do it for cores with an
hash table, as 603 cores don't exhibit that problem and the two isync
increase ./null_syscall selftest by 6 cycles on an MPC 832x.
First problem: unexpected WARN_ON() for mysterious PROTFAULT
WARNING: CPU: 0 PID: 1660 at arch/powerpc/mm/fault.c:354 do_page_fault+0x6c/0x5b0
Modules linked in:
CPU: 0 PID: 1660 Comm: Xorg Not tainted 5.13.0-pmac-00028-gb3c15b60339a #40
NIP: c001b5c8 LR: c001b6f8 CTR: 00000000
REGS: e2d09e40 TRAP: 0700 Not tainted (5.13.0-pmac-00028-gb3c15b60339a)
MSR: 00021032 <ME,IR,DR,RI> CR: 42d04f30 XER: 20000000
GPR00: c000424c e2d09f00 c301b680 e2d09f40 0000001e 42000000 00cba028 00000000
GPR08: 08000000 48000010 c301b680 e2d09f30 22d09f30 00c1fff0 00cba000 a7b7ba4c
GPR16: 00000031 00000000 00000000 00000000 00000000 00000000 a7b7b0d0 00c5c010
GPR24: a7b7b64c a7b7d2f0 00000004 00000000 c1efa6c0 00cba02c 00000300 e2d09f40
NIP [c001b5c8] do_page_fault+0x6c/0x5b0
LR [c001b6f8] do_page_fault+0x19c/0x5b0
Call Trace:
[e2d09f00] [e2d09f04] 0xe2d09f04 (unreliable)
[e2d09f30] [c000424c] DataAccess_virt+0xd4/0xe4
--- interrupt: 300 at 0xa7a261dc
NIP: a7a261dc LR: a7a253bc CTR: 00000000
REGS: e2d09f40 TRAP: 0300 Not tainted (5.13.0-pmac-00028-gb3c15b60339a)
MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 228428e2 XER: 20000000
DAR: 00cba02c DSISR: 42000000
GPR00: a7a27448 afa6b0e0 a74c35c0 a7b7b614 0000001e a7b7b614 00cba028 00000000
GPR08: 00020fd9 00000031 00cb9ff8 a7a273b0 220028e2 00c1fff0 00cba000 a7b7ba4c
GPR16: 00000031 00000000 00000000 00000000 00000000 00000000 a7b7b0d0 00c5c010
GPR24: a7b7b64c a7b7d2f0 00000004 00000002 0000001e a7b7b614 a7b7aff4 00000030
NIP [a7a261dc] 0xa7a261dc
LR [a7a253bc] 0xa7a253bc
--- interrupt: 300
Instruction dump:
7c4a1378 810300a0 75278410 83820298 83a300a4 553b018c 551e0036 4082038c
2e1b0000 40920228 75280800 41820220 <0fe00000> 3b600000 41920214 81420594
Second problem: MSR PR is seen unset allthough the interrupt frame shows it set
kernel BUG at arch/powerpc/kernel/interrupt.c:458!
Oops: Exception in kernel mode, sig: 5 [#1]
BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 PowerMac
Modules linked in:
CPU: 0 PID: 1660 Comm: Xorg Tainted: G W 5.13.0-pmac-00028-gb3c15b60339a #40
NIP: c0011434 LR: c001629c CTR: 00000000
REGS: e2d09e70 TRAP: 0700 Tainted: G W (5.13.0-pmac-00028-gb3c15b60339a)
MSR: 00029032 <EE,ME,IR,DR,RI> CR: 42d09f30 XER: 00000000
GPR00: 00000000 e2d09f30 c301b680 e2d09f40 83440000 c44d0e68 e2d09e8c 00000000
GPR08: 00000002 00dc228a 00004000 e2d09f30 22d09f30 00c1fff0 afa6ceb4 00c26144
GPR16: 00c25fb8 00c26140 afa6ceb8 90000000 00c944d8 0000001c 00000000 00200000
GPR24: 00000000 000001fb afa6d1b4 00000001 00000000 a539a2a0 a530fd80 00000089
NIP [c0011434] interrupt_exit_kernel_prepare+0x10/0x70
LR [c001629c] interrupt_return+0x9c/0x144
Call Trace:
[e2d09f30] [c000424c] DataAccess_virt+0xd4/0xe4 (unreliable)
--- interrupt: 300 at 0xa09be008
NIP: a09be008 LR: a09bdfe8 CTR: a09bdfc0
REGS: e2d09f40 TRAP: 0300 Tainted: G W (5.13.0-pmac-00028-gb3c15b60339a)
MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 420028e2 XER: 20000000
DAR: a539a308 DSISR: 0a000000
GPR00: a7b90d50 afa6b2d0 a74c35c0 a0a8b690 a0a8b698 a5365d70 a4fa82a8 00000004
GPR08: 00000000 a09bdfc0 00000000 a5360000 a09bde7c 00c1fff0 afa6ceb4 00c26144
GPR16: 00c25fb8 00c26140 afa6ceb8 90000000 00c944d8 0000001c 00000000 00200000
GPR24: 00000000 000001fb afa6d1b4 00000001 00000000 a539a2a0 a530fd80 00000089
NIP [a09be008] 0xa09be008
LR [a09bdfe8] 0xa09bdfe8
--- interrupt: 300
Instruction dump:
80010024 83e1001c 7c0803a6 4bffff80 3bc00800 4bffffd0 486b42fd 4bffffcc
81430084 71480002 41820038 554a0462 <0f0a0000> 80620060 74630001 40820034
Fixes: b5efec00b6 ("powerpc/32s: Move KUEP locking/unlocking in C")
Cc: stable@vger.kernel.org # v5.13+
Reported-by: Stan Johnson <userm57@yahoo.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/4856f5574906e2aec0522be17bf3848a22b2cd0b.1629269345.git.christophe.leroy@csgroup.eu
Using asm goto in __WARN_FLAGS() and WARN_ON() allows more
flexibility to GCC.
For that add an entry to the exception table so that
program_check_exception() knowns where to resume execution
after a WARNING.
Here are two exemples. The first one is done on PPC32 (which
benefits from the previous patch), the second is on PPC64.
unsigned long test(struct pt_regs *regs)
{
int ret;
WARN_ON(regs->msr & MSR_PR);
return regs->gpr[3];
}
unsigned long test9w(unsigned long a, unsigned long b)
{
if (WARN_ON(!b))
return 0;
return a / b;
}
Before the patch:
000003a8 <test>:
3a8: 81 23 00 84 lwz r9,132(r3)
3ac: 71 29 40 00 andi. r9,r9,16384
3b0: 40 82 00 0c bne 3bc <test+0x14>
3b4: 80 63 00 0c lwz r3,12(r3)
3b8: 4e 80 00 20 blr
3bc: 0f e0 00 00 twui r0,0
3c0: 80 63 00 0c lwz r3,12(r3)
3c4: 4e 80 00 20 blr
0000000000000bf0 <.test9w>:
bf0: 7c 89 00 74 cntlzd r9,r4
bf4: 79 29 d1 82 rldicl r9,r9,58,6
bf8: 0b 09 00 00 tdnei r9,0
bfc: 2c 24 00 00 cmpdi r4,0
c00: 41 82 00 0c beq c0c <.test9w+0x1c>
c04: 7c 63 23 92 divdu r3,r3,r4
c08: 4e 80 00 20 blr
c0c: 38 60 00 00 li r3,0
c10: 4e 80 00 20 blr
After the patch:
000003a8 <test>:
3a8: 81 23 00 84 lwz r9,132(r3)
3ac: 71 29 40 00 andi. r9,r9,16384
3b0: 40 82 00 0c bne 3bc <test+0x14>
3b4: 80 63 00 0c lwz r3,12(r3)
3b8: 4e 80 00 20 blr
3bc: 0f e0 00 00 twui r0,0
0000000000000c50 <.test9w>:
c50: 7c 89 00 74 cntlzd r9,r4
c54: 79 29 d1 82 rldicl r9,r9,58,6
c58: 0b 09 00 00 tdnei r9,0
c5c: 7c 63 23 92 divdu r3,r3,r4
c60: 4e 80 00 20 blr
c70: 38 60 00 00 li r3,0
c74: 4e 80 00 20 blr
In the first exemple, we see GCC doesn't need to duplicate what
happens after the trap.
In the second exemple, we see that GCC doesn't need to emit a test
and a branch in the likely path in addition to the trap.
We've got some WARN_ON() in .softirqentry.text section so it needs
to be added in the OTHER_TEXT_SECTIONS in modpost.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/389962b1b702e3c78d169e59bcfac56282889173.1618331882.git.christophe.leroy@csgroup.eu
powerpc BUG_ON() and WARN_ON() are based on using twnei instruction.
For catching simple conditions like a variable having value 0, this
is efficient because it does the test and the trap at the same time.
But most conditions used with BUG_ON or WARN_ON are more complex and
forces GCC to format the condition into a 0 or 1 value in a register.
This will usually require 2 to 3 instructions.
The most efficient solution would be to use __builtin_trap() because
GCC is able to optimise the use of the different trap instructions
based on the requested condition, but this is complex if not
impossible for the following reasons:
- __builtin_trap() is a non-recoverable instruction, so it can't be
used for WARN_ON
- Knowing which line of code generated the trap would require the
analysis of DWARF information. This is not a feature we have today.
As mentioned in commit 8d4fbcfbe0 ("Fix WARN_ON() on bitfield ops")
the way WARN_ON() is implemented is suboptimal. That commit also
mentions an issue with 'long long' condition. It fixed it for
WARN_ON() but the same problem still exists today with BUG_ON() on
PPC32. It will be fixed by using the generic implementation.
By using the generic implementation, gcc will naturally generate a
branch to the unconditional trap generated by BUG().
As modern powerpc implement zero-cycle branch,
that's even more efficient.
And for the functions using WARN_ON() and its return, the test
on return from WARN_ON() is now also used for the WARN_ON() itself.
On PPC64 we don't want it because we want to be able to use CFAR
register to track how we entered the code that trapped. The CFAR
register would be clobbered by the branch.
A simple test function:
unsigned long test9w(unsigned long a, unsigned long b)
{
if (WARN_ON(!b))
return 0;
return a / b;
}
Before the patch:
0000046c <test9w>:
46c: 7c 89 00 34 cntlzw r9,r4
470: 55 29 d9 7e rlwinm r9,r9,27,5,31
474: 0f 09 00 00 twnei r9,0
478: 2c 04 00 00 cmpwi r4,0
47c: 41 82 00 0c beq 488 <test9w+0x1c>
480: 7c 63 23 96 divwu r3,r3,r4
484: 4e 80 00 20 blr
488: 38 60 00 00 li r3,0
48c: 4e 80 00 20 blr
After the patch:
00000468 <test9w>:
468: 2c 04 00 00 cmpwi r4,0
46c: 41 82 00 0c beq 478 <test9w+0x10>
470: 7c 63 23 96 divwu r3,r3,r4
474: 4e 80 00 20 blr
478: 0f e0 00 00 twui r0,0
47c: 38 60 00 00 li r3,0
480: 4e 80 00 20 blr
So we see before the patch we need 3 instructions on the likely path
to handle the WARN_ON(). With the patch the trap goes on the unlikely
path.
See below the difference at the entry of system_call_exception where
we have several BUG_ON(), allthough less impressing.
With the patch:
00000000 <system_call_exception>:
0: 81 6a 00 84 lwz r11,132(r10)
4: 90 6a 00 88 stw r3,136(r10)
8: 71 60 00 02 andi. r0,r11,2
c: 41 82 00 70 beq 7c <system_call_exception+0x7c>
10: 71 60 40 00 andi. r0,r11,16384
14: 41 82 00 6c beq 80 <system_call_exception+0x80>
18: 71 6b 80 00 andi. r11,r11,32768
1c: 41 82 00 68 beq 84 <system_call_exception+0x84>
20: 94 21 ff e0 stwu r1,-32(r1)
24: 93 e1 00 1c stw r31,28(r1)
28: 7d 8c 42 e6 mftb r12
...
7c: 0f e0 00 00 twui r0,0
80: 0f e0 00 00 twui r0,0
84: 0f e0 00 00 twui r0,0
Without the patch:
00000000 <system_call_exception>:
0: 94 21 ff e0 stwu r1,-32(r1)
4: 93 e1 00 1c stw r31,28(r1)
8: 90 6a 00 88 stw r3,136(r10)
c: 81 6a 00 84 lwz r11,132(r10)
10: 69 60 00 02 xori r0,r11,2
14: 54 00 ff fe rlwinm r0,r0,31,31,31
18: 0f 00 00 00 twnei r0,0
1c: 69 60 40 00 xori r0,r11,16384
20: 54 00 97 fe rlwinm r0,r0,18,31,31
24: 0f 00 00 00 twnei r0,0
28: 69 6b 80 00 xori r11,r11,32768
2c: 55 6b 8f fe rlwinm r11,r11,17,31,31
30: 0f 0b 00 00 twnei r11,0
34: 7d 8c 42 e6 mftb r12
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b286e07fb771a664b631cd07a40b09c06f26e64b.1618331881.git.christophe.leroy@csgroup.eu
The associativity details of the newly added resourced are collected from
the hypervisor via "ibm,configure-connector" rtas call. Update the numa
distance details of the newly added numa node after the above call.
Instead of updating NUMA distance every time we lookup a node id
from the associativity property, add helpers that can be used
during boot which does this only once. Also remove the distance
update from node id lookup helpers.
Currently, we duplicate parsing code for ibm,associativity and
ibm,associativity-lookup-arrays in the kernel. The associativity array provided
by these device tree properties are very similar and hence can use
a helper to parse the node id and numa distance details.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210812132223.225214-4-aneesh.kumar@linux.ibm.com
On P10, the feature doing an automatic "save & restore" of a VCPU
interrupt context is set by default in OPAL. When a VP context is
pulled out, the state of the interrupt registers are saved by the XIVE
interrupt controller under the internal NVP structure representing the
VP. This saves a costly store/load in guest entries and exits.
If OPAL advertises the "save & restore" feature in the device tree,
it should also have set the 'H' bit in the CAM line. Check that when
vCPUs are connected to their ICP in KVM before going any further.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210720134209.256133-3-clg@kaod.org
pnv_opal_pci_msi_eoi() is called from KVM to EOI passthrough interrupts
when in real mode. Adding MSI domain broke the hack using the
'ioda.irq_chip' field to deduce the owning PHB. Fix that by using the
IRQ chip data in the MSI domain.
The 'ioda.irq_chip' field is now unused and could be removed from the
pnv_phb struct.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701132750.1475580-30-clg@kaod.org
This moves the IRQ initialization done under the different ICS backends
in the common part of XICS. The 'map' handler becomes a simple 'check'
on the HW IRQ at the FW level.
As we don't need an ICS anymore in xics_migrate_irqs_away(), the XICS
domain does not set a chip data for the IRQ.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701132750.1475580-18-clg@kaod.org
The MSI domain clears the IRQ with msi_domain_free(), which calls
irq_domain_free_irqs_top(), which clears the handler data. This is a
problem for the XIVE controller since we need to unmap MMIO pages and
free a specific XIVE structure.
The 'msi_free()' handler is called before irq_domain_free_irqs_top()
when the handler data is still available. Use that to clear the XIVE
controller data.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701132750.1475580-10-clg@kaod.org
Two IRQ domains are added on top of default machine IRQ domain.
First, the top level "pSeries-PCI-MSI" domain deals with the MSI
specificities. In this domain, the HW IRQ numbers are generated by the
PCI MSI layer, they compose a unique ID for an MSI source with the PCI
device identifier and the MSI vector number.
These numbers can be quite large on a pSeries machine running under
the IBM Hypervisor and /sys/kernel/irq/ and /proc/interrupts will
require small fixes to show them correctly.
Second domain is the in-the-middle "pSeries-MSI" domain which acts as
a proxy between the PCI MSI subsystem and the machine IRQ subsystem.
It usually allocate the MSI vector numbers but, on pSeries machines,
this is done by the RTAS FW and RTAS returns IRQ numbers in the IRQ
number space of the machine. This is why the in-the-middle "pSeries-MSI"
domain has the same HW IRQ numbers as its parent domain.
Only the XIVE (P9/P10) parent domain is supported for now. We still
need to add support for IRQ domain hierarchy under XICS.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701132750.1475580-6-clg@kaod.org
This is the same as commit acdad8fb4a ("powerpc: Force inlining of
mmu_has_feature to fix build failure") but for radix_enabled(). The
config in the linked bugzilla causes the following build failure:
LD .tmp_vmlinux.kallsyms1
powerpc64-linux-ld: arch/powerpc/mm/pgtable.o: in function `.__ptep_set_access_flags':
pgtable.c:(.text+0x17c): undefined reference to `.radix__ptep_set_access_flags'
powerpc64-linux-ld: arch/powerpc/mm/pageattr.o: in function `.change_page_attr':
pageattr.c:(.text+0xc0): undefined reference to `.radix__flush_tlb_kernel_range'
etc.
This is due to radix_enabled() not being inlined. See extract from
building with -Winline:
In file included from arch/powerpc/include/asm/lppaca.h:46,
from arch/powerpc/include/asm/paca.h:17,
from arch/powerpc/include/asm/current.h:13,
from include/linux/thread_info.h:23,
from include/asm-generic/preempt.h:5,
from ./arch/powerpc/include/generated/asm/preempt.h:1,
from include/linux/preempt.h:78,
from include/linux/spinlock.h:51,
from include/linux/mmzone.h:8,
from include/linux/gfp.h:6,
from arch/powerpc/mm/pgtable.c:21:
arch/powerpc/include/asm/book3s/64/pgtable.h: In function '__ptep_set_access_flags':
arch/powerpc/include/asm/mmu.h:327:20: error: inlining failed in call to 'radix_enabled': call is unlikely and code size would grow [-Werror=inline]
The code relies on constant folding of MMU_FTRS_POSSIBLE at buildtime
and elimination of non possible parts of code at compile time. For this
to work radix_enabled() must be inlined so make it __always_inline.
Reported-by: Erhard F. <erhard_f@mailbox.org>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Trimmed error messages in change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=213803
Link: https://lore.kernel.org/r/20210804013724.514468-1-jniethe5@gmail.com
After a LPM, the device tree node ibm,dynamic-reconfiguration-memory may be
updated by the hypervisor in the case the NUMA topology of the LPAR's
memory is updated.
This is handled by the kernel, but the memory's node is not updated because
there is no way to move a memory block between nodes from the Linux kernel
point of view.
If later a memory block is added or removed, drmem_update_dt() is called
and it is overwriting the DT node ibm,dynamic-reconfiguration-memory to
match the added or removed LMB. But the LMB's associativity node has not
been updated after the DT node update and thus the node is overwritten by
the Linux's topology instead of the hypervisor one.
Introduce a hook called when the ibm,dynamic-reconfiguration-memory node is
updated to force an update of the LMB's associativity. However, ignore the
call to that hook when the update has been triggered by drmem_update_dt().
Because, in that case, the LMB tree has been used to set the DT property
and thus it doesn't need to be updated back. Since drmem_update_dt() is
called under the protection of the device_hotplug_lock and the hook is
called in the same context, use a simple boolean variable to detect that
call.
Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210517090606.56930-1-ldufour@linux.ibm.com
32 bits BOOKE have special interrupts for debug and other
critical events.
When handling those interrupts, dedicated registers are saved
in the stack frame in addition to the standard registers, leading
to a shift of the pt_regs struct.
Since commit db297c3b07 ("powerpc/32: Don't save thread.regs on
interrupt entry"), the pt_regs struct is expected to be at the
same place all the time.
Instead of handling a special struct in addition to pt_regs, just
add those special registers to struct pt_regs.
Fixes: db297c3b07 ("powerpc/32: Don't save thread.regs on interrupt entry")
Cc: stable@vger.kernel.org
Reported-by: Radu Rendec <radu.rendec@gmail.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/028d5483b4851b01ea4334d0751e7f260419092b.1625637264.git.christophe.leroy@csgroup.eu
On POWER10 systems, the "ibm,thread-groups" property "2" indicates the cpus
in thread-group share both L2 and L3 caches. Hence, use cache_property = 2
itself to find both the L2 and L3 cache siblings.
Hence, create a new thread_group_l3_cache_map to keep list of L3 siblings,
but fill the mask using same property "2" array.
Signed-off-by: Parth Shah <parth@linux.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210728175607.591679-4-parth@linux.ibm.com
Currently the cacheinfo code on powerpc indexes the "cache" objects
(modelling the L1/L2/L3 caches) where the key is device-tree node
corresponding to that cache. On some of the POWER server platforms
thread-groups within the core share different sets of caches (Eg: On
SMT8 POWER9 systems, threads 0,2,4,6 of a core share L1 cache and
threads 1,3,5,7 of the same core share another L1 cache). On such
platforms, there is a single device-tree node corresponding to that
cache and the cache-configuration within the threads of the core is
indicated via "ibm,thread-groups" device-tree property.
Since the current code is not aware of the "ibm,thread-groups"
property, on the aforementoined systems, cacheinfo code still treats
all the threads in the core to be sharing the cache because of the
single device-tree node (In the earlier example, the cacheinfo code
would says CPUs 0-7 share L1 cache).
In this patch, we make the powerpc cacheinfo code aware of the
"ibm,thread-groups" property. We indexe the "cache" objects by the
key-pair (device-tree node, thread-group id). For any CPUX, for a
given level of cache, the thread-group id is defined to be the first
CPU in the "ibm,thread-groups" cache-group containing CPUX. For levels
of cache which are not represented in "ibm,thread-groups" property,
the thread-group id is -1.
[parth: Remove "static" keyword for the definition of "thread_group_l1_cache_map"
and "thread_group_l2_cache_map" to get rid of the compile error.]
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Parth Shah <parth@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210728175607.591679-2-parth@linux.ibm.com
Parts of linux/compat.h are under an #ifdef, but we end up
using more of those over time, moving things around bit by
bit.
To get it over with once and for all, make all of this file
uncondititonal now so it can be accessed everywhere. There
are only a few types left that are in asm/compat.h but not
yet in the asm-generic version, so add those in the process.
This requires providing a few more types in asm-generic/compat.h
that were not already there. The only tricky one is
compat_sigset_t, which needs a little help on 32-bit architectures
and for x86.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
