Commit 07baeb04 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Borislav Petkov
Browse files

x86/fpu: Make __raw_xsave_addr() use a feature number instead of mask 



Most users of __raw_xsave_addr() use a feature number, shift it to a
mask and then __raw_xsave_addr() shifts it back to the feature number.

Make __raw_xsave_addr() use the feature number as an argument.

Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Reviewed-by: default avatarBorislav Petkov <bp@suse.de>
Reviewed-by: default avatarDave Hansen <dave.hansen@intel.com>
Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: kvm ML <kvm@vger.kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190403164156.19645-11-bigeasy@linutronix.de
parent 4ee91519

arch/x86/kernel/fpu/xstate.c

+11 −11
Original line number Diff line number Diff line
@@ -805,20 +805,18 @@ void fpu__resume_cpu(void) 
}



/*

 * Given an xstate feature mask, calculate where in the xsave

 * Given an xstate feature nr, calculate where in the xsave

 * buffer the state is.  Callers should ensure that the buffer

 * is valid.

 */

static void *__raw_xsave_addr(struct xregs_state *xsave, int xstate_feature_mask)

static void *__raw_xsave_addr(struct xregs_state *xsave, int xfeature_nr)

{

	int feature_nr = fls64(xstate_feature_mask) - 1;



	if (!xfeature_enabled(feature_nr)) {

	if (!xfeature_enabled(xfeature_nr)) {

		WARN_ON_FPU(1);

		return NULL;

	}



	return (void *)xsave + xstate_comp_offsets[feature_nr];

	return (void *)xsave + xstate_comp_offsets[xfeature_nr];

}

/*

 * Given the xsave area and a state inside, this function returns the
@@ -840,6 +838,7 @@ static void *__raw_xsave_addr(struct xregs_state *xsave, int xstate_feature_mask 
 */

void *get_xsave_addr(struct xregs_state *xsave, int xstate_feature)

{

	int xfeature_nr;

	/*

	 * Do we even *have* xsave state?

	 */
@@ -867,7 +866,8 @@ void *get_xsave_addr(struct xregs_state *xsave, int xstate_feature) 
	if (!(xsave->header.xfeatures & xstate_feature))

		return NULL;



	return __raw_xsave_addr(xsave, xstate_feature);

	xfeature_nr = fls64(xstate_feature) - 1;

	return __raw_xsave_addr(xsave, xfeature_nr);

}

EXPORT_SYMBOL_GPL(get_xsave_addr);
@@ -1014,7 +1014,7 @@ int copy_xstate_to_kernel(void *kbuf, struct xregs_state *xsave, unsigned int of 
		 * Copy only in-use xstates:

		 */

		if ((header.xfeatures >> i) & 1) {

			void *src = __raw_xsave_addr(xsave, 1 << i);

			void *src = __raw_xsave_addr(xsave, i);



			offset = xstate_offsets[i];

			size = xstate_sizes[i];
@@ -1100,7 +1100,7 @@ int copy_xstate_to_user(void __user *ubuf, struct xregs_state *xsave, unsigned i 
		 * Copy only in-use xstates:

		 */

		if ((header.xfeatures >> i) & 1) {

			void *src = __raw_xsave_addr(xsave, 1 << i);

			void *src = __raw_xsave_addr(xsave, i);



			offset = xstate_offsets[i];

			size = xstate_sizes[i];
@@ -1157,7 +1157,7 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) 
		u64 mask = ((u64)1 << i);



		if (hdr.xfeatures & mask) {

			void *dst = __raw_xsave_addr(xsave, 1 << i);

			void *dst = __raw_xsave_addr(xsave, i);



			offset = xstate_offsets[i];

			size = xstate_sizes[i];
@@ -1211,7 +1211,7 @@ int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf) 
		u64 mask = ((u64)1 << i);



		if (hdr.xfeatures & mask) {

			void *dst = __raw_xsave_addr(xsave, 1 << i);

			void *dst = __raw_xsave_addr(xsave, i);



			offset = xstate_offsets[i];

			size = xstate_sizes[i];

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