Commit 5ced4e53 authored by Reiji Watanabe's avatar Reiji Watanabe Committed by Marc Zyngier
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KVM: arm64: selftests: Add a test case for a linked watchpoint 



Currently, the debug-exceptions test doesn't have a test case for
a linked watchpoint. Add a test case for the linked watchpoint to
the test. The new test case uses the highest numbered context-aware
breakpoint (for Context ID match), and the watchpoint#0, which is
linked to the context-aware breakpoint.

Signed-off-by: default avatarReiji Watanabe <reijiw@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221020054202.2119018-9-reijiw@google.com
parent 14236593

tools/testing/selftests/kvm/aarch64/debug-exceptions.c

+35 −0
Original line number Diff line number Diff line
@@ -22,6 +22,9 @@ 
#define DBGWCR_WR	(0x2 << 3)

#define DBGWCR_EL1	(0x1 << 1)

#define DBGWCR_E	(0x1 << 0)

#define DBGWCR_LBN_SHIFT	16

#define DBGWCR_WT_SHIFT		20

#define DBGWCR_WT_LINK		(0x1 << DBGWCR_WT_SHIFT)



#define SPSR_D		(1 << 9)

#define SPSR_SS		(1 << 21)
@@ -171,6 +174,28 @@ static void install_hw_bp(uint8_t bpn, uint64_t addr) 
	enable_monitor_debug_exceptions();

}



static void install_wp_ctx(uint8_t addr_wp, uint8_t ctx_bp, uint64_t addr,

			   uint64_t ctx)

{

	uint32_t wcr;

	uint64_t ctx_bcr;



	/* Setup a context-aware breakpoint for Linked Context ID Match */

	ctx_bcr = DBGBCR_LEN8 | DBGBCR_EXEC | DBGBCR_EL1 | DBGBCR_E |

		  DBGBCR_BT_CTX_LINK;

	write_dbgbcr(ctx_bp, ctx_bcr);

	write_dbgbvr(ctx_bp, ctx);



	/* Setup a linked watchpoint (linked to the context-aware breakpoint) */

	wcr = DBGWCR_LEN8 | DBGWCR_RD | DBGWCR_WR | DBGWCR_EL1 | DBGWCR_E |

	      DBGWCR_WT_LINK | ((uint32_t)ctx_bp << DBGWCR_LBN_SHIFT);

	write_dbgwcr(addr_wp, wcr);

	write_dbgwvr(addr_wp, addr);

	isb();



	enable_monitor_debug_exceptions();

}



void install_hw_bp_ctx(uint8_t addr_bp, uint8_t ctx_bp, uint64_t addr,

		       uint64_t ctx)

{
@@ -306,6 +331,16 @@ static void guest_code(uint8_t bpn, uint8_t wpn, uint8_t ctx_bpn) 
	write_sysreg(0, contextidr_el1);

	GUEST_ASSERT_EQ(hw_bp_addr, PC(hw_bp_ctx));



	/* Linked watchpoint */

	reset_debug_state();

	install_wp_ctx(wpn, ctx_bpn, PC(write_data), ctx);

	/* Set context id */

	write_sysreg(ctx, contextidr_el1);

	isb();

	write_data = 'x';

	GUEST_ASSERT_EQ(write_data, 'x');

	GUEST_ASSERT_EQ(wp_data_addr, PC(write_data));



	GUEST_DONE();

}