Commit 65c7d070 authored by Nicholas Piggin's avatar Nicholas Piggin Committed by Michael Ellerman
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powerpc/pseries: Get entry and uaccess flush required bits from H_GET_CPU_CHARACTERISTICS 



This allows the hypervisor / firmware to describe these workarounds to
the guest.

Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210503130243.891868-2-npiggin@gmail.com
parent 710e6822

arch/powerpc/include/asm/hvcall.h

+2 −0
Original line number Diff line number Diff line
@@ -400,6 +400,8 @@ 
#define H_CPU_BEHAV_FAVOUR_SECURITY_H	(1ull << 60) // IBM bit 3

#define H_CPU_BEHAV_FLUSH_COUNT_CACHE	(1ull << 58) // IBM bit 5

#define H_CPU_BEHAV_FLUSH_LINK_STACK	(1ull << 57) // IBM bit 6

#define H_CPU_BEHAV_NO_L1D_FLUSH_ENTRY	(1ull << 56) // IBM bit 7

#define H_CPU_BEHAV_NO_L1D_FLUSH_UACCESS (1ull << 55) // IBM bit 8



/* Flag values used in H_REGISTER_PROC_TBL hcall */

#define PROC_TABLE_OP_MASK	0x18

arch/powerpc/platforms/pseries/setup.c

+6 −0
Original line number Diff line number Diff line
@@ -549,6 +549,12 @@ static void init_cpu_char_feature_flags(struct h_cpu_char_result *result) 
	if (!(result->behaviour & H_CPU_BEHAV_L1D_FLUSH_PR))

		security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);



	if (result->behaviour & H_CPU_BEHAV_NO_L1D_FLUSH_ENTRY)

		security_ftr_clear(SEC_FTR_L1D_FLUSH_ENTRY);



	if (result->behaviour & H_CPU_BEHAV_NO_L1D_FLUSH_UACCESS)

		security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS);



	if (!(result->behaviour & H_CPU_BEHAV_BNDS_CHK_SPEC_BAR))

		security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);

}