4.15-stable review patch. If anyone has any objections, please let me know.
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From: Mahesh Salgaonkar mahesh@linux.vnet.ibm.com
commit 8d81296cfcce89013a714feb8d25004a156f8181 upstream.
radix__flush_tlb_all() is called only in kexec path in real mode and any tracepoints at this stage will make kexec to fail if enabled.
To verify enable tlbie trace before kexec.
$ echo 1 > /sys/kernel/debug/tracing/events/powerpc/tlbie/enable == kexec into new kernel and kexec fails.
Fix this by not calling trace_tlbie from radix__flush_tlb_all().
Fixes: 0428491cba92 ("powerpc/mm: Trace tlbie(l) instructions") Cc: stable@vger.kernel.org # v4.13+ Signed-off-by: Mahesh Salgaonkar mahesh@linux.vnet.ibm.com Acked-by: Balbir Singh bsingharora@gmail.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/powerpc/mm/tlb-radix.c | 2 -- 1 file changed, 2 deletions(-)
--- a/arch/powerpc/mm/tlb-radix.c +++ b/arch/powerpc/mm/tlb-radix.c @@ -600,14 +600,12 @@ void radix__flush_tlb_all(void) */ asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1) : : "r"(rb), "i"(r), "i"(1), "i"(ric), "r"(rs) : "memory"); - trace_tlbie(0, 0, rb, rs, ric, prs, r); /* * now flush host entires by passing PRS = 0 and LPID == 0 */ asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1) : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(0) : "memory"); asm volatile("eieio; tlbsync; ptesync": : :"memory"); - trace_tlbie(0, 0, rb, 0, ric, prs, r); }
void radix__flush_tlb_pte_p9_dd1(unsigned long old_pte, struct mm_struct *mm,