From 8fe49b99ff251eac6fae2d326bca286f30f9965f Mon Sep 17 00:00:00 2001
From: Katharine Hyatt <khyatt@flatironinstitute.org>
Date: Mon, 17 Aug 2026 09:19:40 -0400
Subject: [PATCH] Make svd_trunc pullback GPU friendly

---
 src/pullbacks/svd.jl | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/pullbacks/svd.jl b/src/pullbacks/svd.jl
index 4291bf9e6..365ca9feb 100755
--- a/src/pullbacks/svd.jl
+++ b/src/pullbacks/svd.jl
@@ -241,8 +241,9 @@ function svd_trunc_pullback!(
         Y₀ᴴ = iszerotangent(ΔV₊ᴴ) ? zero(Vᴴ) : ldiv!(Diagonal(S), ΔV₊ᴴ)
         US = mul!(ΔAV, U, Smat) # recycle ΔAV
         AP = mul!(copy(A), US, Vᴴ, -1, 1)
-        AP ./= S[end]
-        S⁻¹ = S[end] ./ S
+        minS = minimum(S)
+        AP ./= minS
+        S⁻¹ = minS ./ S
         X₁ = rmul!(AP * Y₀ᴴ', Diagonal(S⁻¹))
         X₁ .+= X₀
         Y₁ᴴ = lmul!(Diagonal(S⁻¹), X₀' * AP)